ASPHALTS 

Their  Sources  and  Utilizations 
1914  ROAD  EDITION 

Containing  Five  New  Chapters  on 

MODERN  ROAD  CONSTRUCTION 


BY 


T.   HUGH  BOOKMAN,  C.E, 

Consulting  Engineer  and  Asphalt  Expert 
Secretary,  Am.  Soc.  EN.  AR.  C. 


PRICE,  TWO    DOLLARS 


NEW  YORK 

THE  WILLIAM  T.  COMSTOCK  CO. 
1914 


-v/S 


COPYRIGHT, 

1908,1914 
BY 

T.  HUGH  BOOKMAN 


CONTENTS 


Chapters 

I. — Discovery  and  Early  Use  of  Asphalt. 

II.— Rock  Asphalt  Mastic  or  Asphalt  Coule. 

III. — Trinidad   Asphalt. 

IV. — Petroleum  Residuum  and  California  Malthas  as  a  Fluxing  Material. 

V. — Venezuela  Asphalts. 

VI. — Cuban  Asphalts. 

VII. — American  Bituminous  Limestone. 

VIII. — Bituminous  Asphalt  Sandstone   Rock. 

IX. — Manjak  and  Uintaite. 

X. — Late   European  Work. 

XL— Turkish   and   Other   Bitumens. 

XII. — Developments  of  Asphalt  Industry  up  to  1903. 

XIII.— Asphalts  in  1908. 

XIV. — Asphalt  in   Building  Construction. 

XV.— Dustless   Roads. 

XVI.— Methods  of  Surfacing  Roads. 

XVII. — Asphaltic   Oils,   Their   Classification   and   Properties. 

XVIII. — Application  of  Asphaltic  Oils. 

XIX. — Sprinkling  with  Asphaltic  Oils. 

XX. — Latest   Views   of    Engineers   on   Asphaltic   Surfacing. 

XXL— Municipal  Asphalt  Plants. 

XXIL— Asphalt  Waterproofing. 

XXI1L— Asphalt  in  Roofing. 

XXIV. — Asphalt  for  Manufacture. 

XXV.— Asphalt  Machinery. 

XXVL— Rock  Asphalt  Maintenance. 

XXVII.— Asphalt   Macadam  Roads. 

XXVIIL— Cold   Laid   Asphalt   Roads. 

XXIX. — Bituminous  Road  Surfaces. 

XXX.— Asphalt   Block   for   Roads. 


PREFACE 

TIS  book  was  suggested    by  a  series  of  articles  that  appeared  some  years 
ago  in  Architecture  and  Building.    Since  the  numbers  containing  these 
articles  ran  out  of  print,  there  has  been  a  continuous  call  for  them, 
and  the  request  was  made  that  they  be  issued  in  book  form. 

The  great  advance  of  late  in  the  asphalt  industry  has  called  for  a  com- 
plete manual  on  the  subject.  This  the  author  has  endeavored  to  furnish,  so 
that  architects,  engineers  and  students  in  the  technical  schools  and  municipal 
officers  having  charge  of  road  construction  may  have  a  reliable  reference 
book  on  the  subject. 

As  will  be  seen,  many  new  features  in  the  exploitation  and  utilization  of 
asphalt  have  arisen  during  the  first  eight  years  of  this  century;  and  un- 
doubtedly the  greatest  demand  yet  known  is  still  to  come  for  the  purpose  of 
surfacing  dustless  roads.  This  line  of  work  is  very  fully  treated  of,  and,  to 
the  author's  mind,  is  the  question  of  the  day. 

I  have  endeavored,  without  fear  or  favor,  to  give  credit  to  all  producers 
of  asphalt  in  every  country  and  clime  and  to  give  to  all  their  due.  I  have 
made  no  comparisons  of  asphalts  as  against  other  materials,  although  some 
of  my  sources  of  information  may  have  incidentally  given  statements  showing 
the  superiority  of  asphalt  over  other  materials  for  waterproofing,  etc. 

This  book  is  the  result  of  thirty-six  years  of  active  life  among  asphalt 
mine  owners,  refiners,  importers,  exporters,  manufacturers  and  contractors, 
and,  as  will  be  seen,  has  taken  me  to  many  countries,  in  all  of  which  I  have 
endeavored  to  glean  information  from  all  interested,  from  presidents  of 
corporations  to  the  humblest  stirrer  of  an  asphalt  kettle. 

To  give  due  credit  to  all  to  whom  I  am  indebted  for  information  would 
well  nigh  call  for  an  additional  volume.  At  the  risk  of  seeming  ungrateful 
to  the  many,  I  wish  to  record  special  obligations  to  the  late  Leon  Malo,  C.  E., 
and  his  coadjutor  W.  H.  Delano,  C.  E.,  to  the  "Good  Roads  Magazine," 
"Municipal  Engineering,"  and  other  technical  journals;  principally  to  the 
efficient,  painstaking  officials  of  the  Bureau  of  Public  Roads  of  the  Depart- 
ment of  Agriculture,  whose  work  in  helping  the  people  of  the  United  States 
to  utilize  their  opportunities  for  building  "goods  roads"  in  the  various  sections 
of  the  country  cannot  be  too  highly  spoken  of ;  and  last,  but  not  least,  to  my 
worthy  publisher,  W.  T.  Comstock,  and  to  my  son,  Kitchell  Monckton 
Boorman. 

T.    HUGH   BOORMAN. 

NEW  YORK,  Sept.  14, 1908. 


PREFACE   TO    SECOND   EDITION 

Since  the  first  edition  of  "Asphalts"  went  to  print,  there  have  beea 
three  International  Conventions  on  Road  Construction,  held  respectively 
at  Paris,  Brussels  and  London. 

Conventions  of  National,  State  and  minor  sections  have  been  too 
numerous  to  mention;  the  knowledge  disseminated  at  these  many  meetings 
has  been  extensive  and  interesting.  The  general  tenor  of  the  discussions 
has  created  a  heavy  demand  for  asphalts  of  all  descriptions  and  the  com- 
mercial interests  involved  are  now  very  heavy.  Some  of  the  older  known 
asphalts  have  become  discredited  to  a  great  extent  and  the  user  of  asphalts 
has  now  many  opportunities  of  purchasing  materials,  capable  of  meeting 
any  specifications  drawn  by  conscientious  engineers. 

I  have  been  frequently  asked  if  I  made  any  statements  in  the  1908 
edition  which  I  should  wish  now  to  modify.  I  am  glad  to  state  that  I 
can  stand  today  for  everything  I  wrote  that  year. 

Along  the  line  of  road  work  many  developments  have  taken  place,  and 
in  the  five  new  chapters  of  this  edition  I  have  striven  to  give  some  of  the 
new  methods  of  construction  evolved  since  1908. 

I  have  endeavored  by  attending  conventions,  college  and  engineering 
society's  lectures,  and  by  careful  reading  of  the  technical  journals,  and  by 
revisiting  England,  to  keep  in  touch  with  all  improvement  in  street  and 
road  construction  which  have  been  developed  since  the  time  of  the  first 
edition. 

In  the  immense  amount  of  treatises  and  papers  on  bituminous  con- 
struction presented  before  conventions,  engineers'  associations  and  colleges, 
it  is  lamentable  to  find  how  few  can  be  received  as  from  unbiased  sources. 
This  is  the  day  of  astute  advertising,  and  in  addition  to  their  regularly 
paid  employes,  such  as  consulting  engineers,  chemists  and  salesmen,  the 
large  corporations  subsidize  to  an  immense  extent  the  daily  and  technical 
press  so  that  the  unsuspecting  layman  seeking  information  on  asphalt,  is 
apt  to  be  misled  through  statements  of  merits  of  individual  brands  of 
asphalts,  emanating  from  such  clever  salesmen  with  their  various  titles 
ranging  from  college  professors  to  daily  news  reporters.  The  most  flagrant 
advertising  dodge  was  that  of  an  asphalt  company  who  offered  a  premium 
of  $100  to  be  awarded  to  the  highway  college  student  who  produced  the 
best  treatise  on  asphalt. 

A  recent  clipping  from  an  unknown  source  affords  an  interesting  if 
not  instructive  statement  of  the  use  of  asphalt  in  "ye  olden  tymes" : 

There  was  nothing  slow  about  the  ancient  Romans.  They  used  a  cement 
the  formula  for  which  many  a  manufacturer  would  be  glad  to  have.  They 
built  roads  so  costly  as  to  make  the  modern  politician  green  with  envy. 
They  even  were  acquainted  with  asphalt  and  bitumen.  Tacitus,  writing 
about  55  B.  C,  describes  this  material  as  follows : 


"At  a  stated  season  of  the  year,  the  lake  throws  up  bitumen.  Experi- 
ence, the  mother  of  all  useful  arts,  has  taught  men  the  method  of  gathering 
it.  It  is  a  liquid  substance,  naturally  of  a  black  hue,  and  by  sprinkling 
vinegar  upon  it,  it  floats  on  the  surface  in  a  condensed  mass,  which  those, 
whose  business  it  is,  lay  hold  of  with  the  hand,  and  draw  to  the  upper 
parts  of  the  vessel;  thence  it  continues  to  flow  in  and  load  the  vessel,  till 
you  cut  it  off.  Nor  could  you  cut  it  off  with  brass  or  iron.  It  shrinks 
from  the  touch  of  blood."  *  *  * 

T.    HUGH    BOOKMAN. 
NBW  YORK,  April  25,  19)4. 


CHAPTER  I. 
DISCOVERY  AND  EARLY  USE  OF  ASPHALT. 


CONSIDERING  the  importance  of  the  subject  little  has  been 
published  in  regard  to  the  material  known  by  the  generic 
name  of  asphalt.  A  few  books  and  many  short  papers  read  before 
engineering  societies,  prepared  for  technical  journals  or  for  the  cir- 
culars of  asphalt  companies,  comprise,  generally  speaking,  the  litera- 
ture on  the  subject.  These  have  been  written  almost  exclusively 
by  engineers  in  the  employ  of  special  companies  or  others  finan- 
cially interested  in  particular  asphalt  deposits  or  mines,  and  so 
necessarily  have  dealt  with  the  subject  within  a  much  confined 
limit. 

It  is  proposed  in  this  book  to  discuss  the  various  kinds  of 
asphalt  and  their  adaptability  for  different  methods  of  construction. 
In  the  first  place  all  disputes  on  the  nomenclature  of  asphalts  must 
be  avoided  and  the  fact  conceded  that  the  hydro-carbons,  viz.,  as- 
phalt, bitumen,  and  maltha,  are  synonymous,  while  differing  in 
chemical  composition.  I  am  the  more  anxious  to  take  this  ground, 
as  in  going  back  to  the  earliest  times  in  which  asphalt  is  known  to 
have  been  used  it  is  necessary  to  refer  to  the  mineral  pitch,  or  bitu- 
men, as  being  the  material  quoted.  The  first  use  of  asphalt  spoken 
of  was  the  cementing  in  the  erection  of  the  Tower  of  Babel ;  next 
we  read  that  Noah  pitched  the  Ark  within  and  without,  "bituminabis 
cum  bitumine,"  says  the  Vulgate,  and  also  in  Genesis  we  read,  "Et 
asphaltus  fuit  eis  vice  cimenti."  The  great  law-giver,  Moses,  was 
preserved  from  death  at  the  suggestion  of  the  Egyptian  Princess,  in 
a  basket  rendered  waterproof  by  bitumen. 

Felltham  wrote  in  the  beginning  of  the  I7th  century  of  the 
"Bituminated  walls  of  Babylon;"  the  source  of  its  supply,  the 
fountains  of  Is,  on  a  tributary  of  the  Euphrates,  still  yields  asphalt. 

Xenophon  in  his  Anabasis  speaks  of  the  Median  Wall  as  being 


io  :  ASPHALTS.  [CHAP.  i. 

built  of  "Burnt  brick  laid  in  asphalt."  Diodorus  Siculus  describes 
the  process  of  laying  the  walls  of  Nineveh  with  material  from  the 
same  source.  He  says :  "In  order  to  bind  the  bricks  they  were  cov- 
ered with  a  layer  of  asphalt,  instead  of  simple  tempered  clay,  and 
were  arranged  in  courses,  and  between  each  thirteenth  course  a  bed 
of  reed  canes  was  introduced."  Diderot's  Encyclopedia  attributes 
the  burning  of  Sodom  and  Gomorrah  to  the  accidental  ignition  of 
petroleum  or  bitumen,  but  the  word  petroleum  not  having  been 
known  to  ancient  writers,  the  legend  probably  refers  to  maltha  or 
bitumen.  Other  ancient  authors  mentioning  asphalt  were  Herod- 
otus, Aristotle,  Strabo,  Pliny  and  Homer. 

The  Egyptians  made  extensive  use  of  bitumen ;  it  was  spread 
upon  the  bandages  wound  around  their  mummies,  and  its  wonderful 
preservative  properties  can  be  seen  in  our  museums,  where  so  many 
of  their  illustrous  dead  now  have  their  abiding  place.  Asphalt  was 
also  used  by  the  Egyptians  in  the  foundations  of  the  Pyramids,  and 
for  the  coating  of  the  external  and  internal  walls  of  the  ground 
floors  of  houses,  and  in  the  construction  of  cisterns,  silos  and  other 
work  where  waterproofing  was  necessary.  Therefore,  from  be- 
fore the  time  of  the  Deluge,  asphalt  has  been  used  and  referred  to, 
and  it  is  no  new  subject  to  be  considered. 

During  the  Middle  Ages  we  read  nothing  of  its  use,  and  not 
until  1721  do  we  hear  of  a  treatise  on  asphalt  being  written  by 
Eyrini  d'  Eyrinis,  professor  of  Greek,  doctor  of  medicine,  in  which 
he  wrote  in  a  half  serious.,  half-humorous  manner  of  its  uses  for 
building  purposes,  and  claimed  it  as  a  panacea  for  almost  every 
sickness.  This  treatise,  I  understand,  was  reprinted  by  M.  Leon 
Malo,  C.  E.,  the  most  able  exponent  of  the  Rock  Asphalt  industry, 
and  to  whose  works  I  shall  have  to  refer  frequently. 

The  asphalt  beds,  or  mine,  which  were  discovered  by  Dr. 
d'Eyrinis  in  1710  were  those  of  the  Val  de  Travers,  in  the  Canton 
of  Neuchatel.  The  doctor  recommends  the  material,  describing  it 
as  "Peculiarly  suitable  for  covering  all  kinds  of  construction,  to 
protect  wood  and  stone  work  against  decay,  worms  and  the  ravages 
of  time,  rendering  them  almost  indestructible,  even  when  exposed 
to  wind,  wet  and  extreme  variations  of  temperature." 

d'Eyrinis  succeeded  in  using  it  with  good  effect  for  the  lining 
of  cisterns  and  walls,  as  a  cementing  material,  and  for  the  flooring 
of  warehouses,  etc. 

After  some  time  the  material  fell  into  disuse;  the  quarries  of 


"ASPHALT  S' 


DISCOVERY  AND   EARLY   USE.  n 

Val  de  Travers  were  even  forgotten,  and  it  was  not  till  the  year 
1832  that  the  material  was  again  prominently  and  successfully  rein- 
troduced;  the  credit  on  this  occasion  being  given  to  the  Count 
Sassenay,  and  in  1838  the  first  asphalt  sidewalks  were  laid  in  Paris. 
The  rock  asphalt  seems  to  have  been  used  in  its  mastic  form  for 
sidewalks  and  floorwork  up  to  the  year  1854,  when  M.  Vaudry  laid 
the  first  compressed  rock  asphalt  roadway  in  Paris.  The  earliest 
knowledge  of  the  adaptability  of  asphalt  for  this  purpose  seems, 
from  M.  Malo's  account,  due  to  the  perspicuity  of  a  Swiss  engineer, 
M.  Merian,  who,  in  1849,  found  that  in  summer  the  pieces  of  rock 
that  fell  from  the  carts  in  traversing  the  road  between  the  mine  and 
the  mastic  works  at  the  village  of  Travers  compressed  under .  the 
wheels ;  he  put  this  lesson  to  profit  by  constructing  a  macadam  road 
of  crude  rock  asphalt,  which  was  compacted  with  a  roller.  In  spite 
of  the  instability  of  its  foundation  and  the  irregularity  of  its  main- 
tenance the  road  was  reported  by  M.  Malo  as  in  good  order  in  1866. 
From  the  Rock  Asphalt  Mines,  therefore,  it  may  be  considered 
that  there  was  started  the  great  industry  of  asphalt  street  pave- 
nients,  which  add  so  much  to  the  appearance  and  health  of  our  mod- 
ern cities.  Under  these  circumstances  it  seems  only  right  to  first 
take  up  the  subject  of  Natural  Rock  Asphalt.  It  was,  I  believe, 
first  brought  prominently  before  the  notice  of  the  American  Engi- 
neers by  Mr.  Edward  P.  North,  C.  E.,  who,  in  a  paper  read  on 
April  16,  1879,  before  the  American  Society  of  Civil  Engineers,  on 
"The  Construction  and  Maintenance  of  Roads,"  gave  his  impression 
from  observation  and  information  acquired  by  him  on  the  subject 
of  asphalt  streets  in  London  and  Paris. 

Compressed  Neuchatel  rock  asphalt  was,  however,  laid  in  New 
York,  in  Union  Square,  in  1872,  the  writer  having  taken  part  in 
the  actual  work  of  laying  it.  This  pavement,  however,  owing  to  a 
lack  of  heavy  traffic,  did  not  prove  a  success,  and  some  ten  years 
later  it  was  replaced  with  asphalt  mastic,  which  was  partly  manu- 
factured frqm  the  old  rock  pavement.  The  original  company  laying 
the  work  became  financially  embarrassed  and  went  into  the  hands 
of  receivers,  and  it  was  under  orders  of  the  latter  that  four  blocks 
of  Natural  Rock  Asphalt  streets  were  laid  on  Pennsylvania  avenue, 
Washington,  with  Neuchatel  rock  in  1876.  This  pavement,  how- 
ever, not  having  any  company  to  look  after  its  maintenance,  was 
repaired  with  Trinidad  asphalt  mixture,  with  which  material  eventu- 
ally it  was  entirely  resurfaced. 


12  ASPHALTS.  [CHAP.  i. 

Three  or  four  years  later  the  Neuchatel  Asphalt  Company,  of 
London,  owners  of  the  Val  de  Travers'  concession,  sent  over  as 
their  representative  the  late  Captain  Henry  R.  Bradbury,  who 
supervised  the  laying  of  Neuchatel  rock  pavement  in  front  of  the 
Brevoort  House  and  Hotel  Victoria,  on  Fifth  avenue,  New  York; 
his  successor  in  the  American  management,  Mr.  Robert  Butcher, 
found  that  the  prices  attainable  for  the  work  here  did  not  compare 
favorably  with  those  obtained  in  European  cities,  and  has  not  fol- 
lowed up  street  pavement  work. 

In  1892  the  Compagnie  G^nerale  des  Asphalte  de  France  es- 
tablished a  model  rock  asphalt  plant  at  Long  Island  City,  and  un- 
der the  management  of  the  author  from  1895  to  1900  some  28,000 
square  yards  of  compressed  asphalt  were  laid  in  New  York,  and 
about  15,000  square  yards  in  Brooklyn.  During  this  period  a  large 
amount  of  rock  asphalt  was  also  supplied  from  the  Seyssel  and 
Ragusa  mines  for  use  on  streets  in  Philadelphia,  Boston  and  Mon- 
treal. 

The  generally  recognized  standard  European  rock  asphalts  are 
those  of  Seyssel,  in  the  Department  of  Ain,  France,  and  the  Val  de 
Travers,  in  the  Canton  of  Neuchatel,  Switzerland.  Important  de- 
posits are  now  being  operated  at  Ragusa,  Sicily;  four  companies 
are  working  adjacent  mines,  viz. :  The  Val  de  Travers  Asphalt 
Paving  of  London,  the  United  Limmer  &  Vorvohle  Rock  Asphalt 
Co.,  the  Societa  Sicula  per  L'Explotazione  Dell  Asfalta  Naturale 
Sicilians,  Palermo,  and  H.  &  A.  B.  Aveline  Catania,  exporting  large 
quantities  to  Europe  and  America,  their  shipping  ports  being  Maz- 
zarelli,  Syracuse  and  Catania — other  deposits  are  found  at  Mons, 
Department  of  Card,  France;  Lobsann,  in  Alsace;  Limmer,  near 
Hanover,  Germany;  San  Valentino,  Province  of  Chieti,  Italy; 
Maestu,  in  Spain,  and  in  several  parts  of  the  United  States,  which, 
of  late,  having  become  quite  an  important  feature  in  the  asphalt 
industry,  will  be  considered  in  full  in  a  subsequent  chapter.  Mr. 
W.  H.  Delano,  of  Paris,  in  his  "Twenty  Years'  Practical  Experi- 
ence of  Natural  Asphalt  and  Mineral  Bitumen,"  published  in  1893, 
gives  the  analysis  of  natural  rock  asphalt  as  follows:  As  mined, 
the  rock  should  be  of  a  chocolate  color,  fine  in  grain,  evenly  im- 
pregnated with  bitumen,  free  from  sulphur,  pyrites,  clay,  sand  and 
of  other  extraneous  matter.  When  examining  with  microscope 
always  look  at  a  fresh  fracture.  Rich  Val  de  Travers  rock,  con- 
taining, say  ii  to  13  per  cent,  bitumen,  should  be  mixed  with  equal 


I 


a* 

o   M 

I* 

P  s 

3  a 

•    H 


'A  S  P  H  A  L  T  S' 


DISCOVERY  AND   EARLY   USE.  13 

parts  of  fine  Seyssel  rock  containing  7  per  cent,  of  bitumen,  which 
is  fixed  and  invariable,  producing  thus : 

ii  +  7 

=9  per  cent,  powder,  suitable  for  a  climate  like  that  of  Lon- 

2 

don.  The  same  may  be  done  with  Ragusa  (Sicilian  rock),  which  is 
rich  in  bitumen  of  excellent  quality,  only  the  texture  or  grain  of  the 
limestone  is  loose,  whereas  that  of  Seyssel  is  fine  and  dense.  Mons 
and  St.  Jean  de  Marejols  asphalts  are  similar  in  structure  to  Ra- 
gusa, but  the  limestone  is  much  finer. 

The  rough  and  ready  way  of  testing  rock  asphalt  is  to  dissolve 
a  sample  of  its  powder  taken  from  three-ton  bulk,  in  carbon  bisul- 
phide, turpentine,  or  ether.  After  stirring  this  well  with  a  glass 
rod,  strain  it  through  a  thick  paper  filter;  then  let  the  sulphide 
evaporate,  which  it  will  do  at  70  degrees ;  weigh  the  bitumen  and  the 
residuum,  afterwards  washing  the  latter  in  hydrochloric  acid,  which 
will  cause  the  lime  to  effervesce,  leaving  any  residue  of  silica, 
pyrites,  etc. ;  but  for  an  absolute  test  an  analyst  accustomed  to 
hydro-carbons  should  be  called. in. 

In  connection  with  this  the  following  tables,  showing  the 
comparative  analyses  of  asphalts,  are  given  on  the  next  page. 
They  were  prepared  by  Col.  James  W.  Howard,  B.  L.,  C.  E. 

The  rock  asphalt  industry  may  be  divided  into  two  branches. 
The  "comprime,"  or  compressed  work,  and  the  "coule,"  or  mastic 
work.  For  streets  the  compressed  asphalt  is  used.  The  rock  in  its 
crude  condition  is  placed  in  a  crusher  and  reduced  to  small  pieces 
and  then  passed  through  a  disintegrater  and  reduced  to  a  powder; 
it  then  passes  through  a  twenty-mesh  sieve,  nothing  being  added  to 
or  taken  from  the  powder  obtained  by  grinding  the  bituminous  rock. 
The  powder  should  contain  not  less  than  9  per  cent,  of  natural  bitu- 
men. The  powder  is  then  heated  in  a  suitable  apparatus  to  200  de- 
gress to  250  degrees  Fahrenheit,  and  must  be  brought  to  the  street 
at  a  temperature  of  not  Iss  than  180  degrees  Fahrenheit  in  carts 
made  for  the  purpose,  and  carefully  spread  to  such  depth  that  after 
having  received  its  ultimate  compression  it  will  have  a  thickness 
of  two  inches.  The  surface  is  rendered  perfectly  even  by  tamping, 
smoothing  and  rolling  with  heated  appliances  of  approved  design. 
This  surface  should  invariably  be  laid  on  a  foundation  of  six  inches 
of  Portland  cement  concrete. 


ASPHALTS. 


[CHAP.  i. 


TABLE  I. 


ANALYSES    OF    CRUDE    ASPHALTUM   FROM  A  FEW  COUNTRIES,  ETC. 


California. 

Bitumen    38  to  85% 

Mineral   matter    60  to    8 

Organic    matter 1 

Water    .  2  to    6 


Cuba. 

24  to  68% 

73  to  26 

2  to    1 

Ito    5 


Mexico. 
35  to  94% 
55  to    4 

8  to    2 

2 


Trinidad. 
35  to  40% 
41  to  26 
10  to    4 
14  to  30 


Venezuela. 
45  to  95% 
40  to  2 

7  to    1 

8  to    2 


Total   per  cent...  100%  100%      100%  100%       100%  100%       100%  100%      100%  100% 


ANALYSES    OF  ASPHALT    ROCK   FROM  A   FEW   COUNTRIES,    ETC. 


California. 
Various. 


Indian  Ter. 
Various'. 


Kentucky. 
Various. 

% 
4. 


Texas. 
Various. 


Utah. 
Various. 


Bitumen     6.47  to  29.60  3.0    to  12.30  4.      to  10.70  3.11  to  11.65     6.34  to  36.28 

Calcium    Carbonate                 9.10  80.00       90.30  to    0.03     8.02  to  29.52 

Silica     89.73  to  45. 40  96.90  to    4.43  95.63  to  89.30  88.32   82.87  to    6.46 

Alumina,     etc 15.90  0.10  to    1.11       6.0                                  27.74 

Magnesium    carbon- 
ate       1.86       0.3 

Miscellaneous     ...  3.80  0.30  0.37  0.29                    2.77 


Total  per  cent 100%    100%    100%    100% 


100%    100%    100%    100%     100%    100% 
J.  W.  HOWARD,  B.  L.,  C.  E, 


TABLE  II. 


"CLASSIFICATION  AND  LOCATION  OF  CERTAIN 

COMPOUNDS. 


IMPORTANT    BITUMENS    AND 


GLANCE-PITCH,  ASPHALTUM,  MALTHA. 

ASPHALT    AND    BITUMINOUS    ROCK. 

Pure  or  Nearly  Pure 
(with      Small      Per 

Compounded     with 
Earthy       Matter 

Compounded      with 
Limestone  (Contain- 

Compounded     with 
Sandstone  (Contain- 

Cent, of  Mineral  and 

(Large  Per  Cent,  of 

ing  Silicates,  etc.). 

ing      Carbonate     of 

Organic  Matter). 

Silicates,     Alumina, 

Lime,   etc.). 

etc.). 

Argentina. 

Argentina. 

Austria. 

France. 

Barbadoes. 

Australia. 

Cuba. 

Germany. 

China. 

Barbadoes. 

France. 

Italy. 

Cuba. 

China. 

Germany. 

Russia. 

Egypt. 

Colombia. 

Hungary. 

Sicily. 

Equador. 

Cuba. 

Italy. 

Spain. 

Honduras. 

Egypt. 

Russia. 

Turkey. 

Japan. 

Equador. 

Sicily. 

United  States. 

Mexico. 

France. 

,      Spain. 

Russia. 

Germany. 

Switzerland. 

Syria. 

Honduras. 

Turkey. 

Turkey. 

Japan. 

United  States. 

United  States. 

Mexico. 

Venezuela. 

Peru. 

Russia. 

Syria. 

Trinidad. 

Turkey. 

United  States. 

Venezuela. 

*From  Paper  on  "ASPHALTUM"  by  J.   W.   Howard  of  New  York,   at  convention 
of   the  American   Society  of   Municipal   Engineers. 


CHAPTER  II. 
ROCK  ASPHALT  MASTIC  OR  ASPHALT  COULE. 


ROCK  asphalt  mastic,  or  asphalt  coule,  as  it  should  more  prop- 
erly be  called,  forms  a  most  important  branch  of  the  asphalt 
industry,  Dr.  d'Eyrinis  was  its  first  exponent,  and  so  far  as  I  know 
Dr.  Jeno  Kovacs  the  last,  the  latter,  in  his  report  on  asphalt  read 
in  1901  before  the  Budapest  congress  of  the  "International  Associa- 
tion for  the  Testing  of  Materials."  The  term  mastic  I  must  state 
is  most  misleading,  and  I  fail  to  find  how  the  term  originated.  The 
word  is  French,  not  English.  The  Anglican  noun  "mastic"  dis- 
tinctly applies  to  the  resinous  substance  obtained  from  the  mastic 
tree,  or  to  a  kind  of  mortar  composed  of  finely-ground  oolitic  lime- 
stone mixed  with  sand  and  litharge  and  used  with  a  considerable 
portion  of  linseed  oil;  hence  frequent  confusion  when  the  word 
mastic  is  used  in  specifications.  The  French  word  "mastic"  is  used 
for  cement,  and  is  more  applicable.  Still,  with  the  innumerable 
cements  used  in  construction,  it  would  seem  better  to  refer  to 
coule,  or  melted  asphalt,  when  speaking  of  the  use  of  asphalt  in 
other  than  its  powdered  form.  The  preparation  of  asphalt  coule 
is  as  follows : 

The  rock,  after  being  reduced  to  a  powder,  is  placed  in  cylin- 
drical kettles,  in  which  about  8  per  cent,  of  Trinidad  asphalt  has 
previously  been  placed  and  melted.  The  mass  is  stirred  by  revolv- 
ing arms  and  agitators  at  a  temperature  of  about  350  degrees  F. 
for  about  nine  hours.  It  is  thus  thoroughly  "cooked,"  and  is  then 
run  out  of  the  kettles  into  moulds,  where  it  cools  in  the  form  of 
cakes  or  blocks,  weighing  from  56  to  60  pounds  each.  These  are 
stamped  with  the  brands  of  the  mines.  The  mastic  so  prepared 
should  show  an  analysis  about  as  follows : 

Bitmumen I4-5O  per  cent 

Carbonate   of   lime 85.00     "       " 

Silica,  alumina  and  oxide  of  iron.       .50     "       " 

IOO.OO 


16.  ASPHALTS. 


[CHAP.  ii. 


To  use  it  for  walks  or  floors  the  blocks  are  broken  up  and  again 
heated  in  suitable  kettles  and  mixed  with  fine  gravel  or  sand  and 
Trinidad  in  the  following  proportions: 

Mastic  blocks  (broken) 60  Ibs. 

Trinidad   asphalt 4     " 

Fine  gravel  and  sand 36     " 

100 

This  is  "cooked"  for  about  five  hours  at  a  temperature  of  about 
360  degrees  F.,  great  care  being  taken  constantly  to  stir  the  mix- 
ture. It  is  then  taken  out  of  the  kettle  by  the  bucketful  and  poured 
on  the  foundation  prepared,  its  consistency  being  such  that  it  will 
flow  very  slowly.  It  is  then  spread  by  means  of  wooden  trowels 
and  compressed  and  smoothed  by  rubbing,  as  in  plastering.  Soon 
after  the  introduction  of  asphalt  coule  in  Paris  it  was  introduced 
into  the  United  States  by  a  Philadelphia  architect.  The  floors  of 
the  portico  of  the  old  Philadelphia  Merchants'  Exchange  were  laid 
with  it  about  the  year  1838,  as  stated  by  me  in  my  paper  on  "Asphalt 
in  Building  Construction,"  read  before  the  Brooklyn  Architectural 
Students'  League,,  May  14,  1890.  Subsequently  the  War  Depart- 
ment imported  the  material  for  covering  the  arches  over  casements 
and  magazines  in  some  of  the  forts,  of  which  Fort  William,  on 
Governor's  Island,  was  one.  The  great  fire  in  Boston  in  1872  first 
drew  my  attention  to  the  desirable  qualities  of  asphalt  as  a  fireproof 
covering  for  roofs,  and  I  introduced  its  use  there  in  1873.  That 
this  material  is  a  most  effective  fireproof  protection  should  be 
recognized. 

In  1835  a  number  of  the  inhabitants  of  the  city  of  Bordeaux 
certified  that  at  the  time  of  the  conflagration  of  the  Bazaar  Borde- 
lais,  which  happened  on  December  28th  of  that  year,  a  number  of 
burning  beams,  rafters  and  other  bodies  in  flames  fell  on  that  part 
of  the  building  covered  with  asphalt  without  causing  it  to  melt,  and 
further  attested  that  the  said  roof  so  covered  had  not  been  injured 
to  any  material  degree.  Of  the  great  fire  in  Hamburg  in  1842, 
which  destroyed,  with  other  buildings,  the  Church  of  St.  Nicholas, 
the  London  "Times"  of  the  28th  of  May  of  that  year,  said : 

"It  was  remarked  as  a  singular  circumstance  during  the  con- 
flagration that  roofs  covered  with  asphalt,  of  which  there  are  some 
here,  opposed  rather  than  encouraged  the  progress  of  the  flames. 


CITY  HALL,    PHILADELPHIA. 
Roofs  and  corridors  laid  with  Asphalt  Coule  by  The  Vulcanite   Paving  Company. 


"A  S  P  II  A  LT  S* 


ROCK  ASPHALT  MASTIC.  17 

It  was  imagined  on  account  of  the  substance  of  which  these  roofs 
were  composed  that  they  would  easily  catch  fire  and  be  the  cause 
of  great  mischief.  Such,  however,  was  not  the  case,  for  it  appears 
that  the  fire  had  little  or  no  effect  on  them,  and  when  the  roofs  of 
the  houses  fell  in,  the  asphalte,  in  which  a  sort  of  rubble  is  mixed 
up,  was  found  to  have  resisted  the  effects  of  the  heat,  and,  like  a 
mass  of  dirt,  served  rather  to  smother  the  flames  than  to  give  them 
increased  vitality." 

Very  exhaustive  tests  were  made  for  The  Omnibus  Co.  of 
Paris  in  1868  by  MM.  Flachat  and  Noissette,  who  submitted  the 
results  to  the  French  Society  of  Civil  Engineers.  The  insurance 
companies  in  the  United  States  give  special  rates  where  asphalt 
is  used  for  roofs. 

The  specifications  usually  read: 

"For  roofs  on  concrete  .foundations  properly  leveled  and 
graded,  lay  one  inch  of  Seyssel  or  Neuchatel  rock  asphalt  mastic, 
applied  in  two  coats,  on  three  thicknesses  of  roofing  felt  cemented 
with  asphalt." 

Copper  flashing  should  always  be  specified  in  connection  with 
this  roofing.  The  roof  of  the  Philadelphia  City  Hall  was  laid  by 
the  Vulcanite  Paving  Co.  with  asphalt  mastic,  and  the  same  material 
was  used  in  the  corridors  of  the  building.  The  use  of  asphalt  coule 
is  by  no  means  confined  to  roofs ;  it  is  a  desirable  material  for  con- 
struction, from  the  damp  course  in  the  foundation  of  a  building  to 
the  roof  on  the  top  of  the  same.  Used  as  a  damp  course  in  the  foun- 
dation, it  arrests  absolutely  the  capillary  attraction  that  is  so  fatal 
to  many  buildings  and  renders  them  unhealthy  through  dampness. 
Cellars  should  be  floored  with  asphalt  so  as  to  insure  dryness  and 
health. 

As  flooring  for  use  in  hospitals,  lavatories,  laboratories,  laun- 
dries, refineries  and  mills  it  stands  without  a  peer.  It  is  impene- 
trable by  moisture  ,and  will  not  crack  from  settlement  of  masonry, 
as  will  rigid  and  unyielding  substance  like  artificial  stone  made 
from  cement.  Its  characteristic  of  elasticity  allows  it  to  take  up 
the  varying  strains  and  settlements  that  will  occur  in  any  masonry 
without  cracking.  Used  as  a  foundation  under  heavy  machinery, 
it  absorbs  all  vibration  and  makes  possible  the  mounting  of  the 
heaviest  machinery  in  closely  crowded  quarters.  As  a  flooring  for 
railway  stations,  it  will  stand  without  cracking  or  splitting  the  im- 
pact of  heavy  blows  from  the  dropping  of  baggage;  it  is  not  slip- 


i8  ASPHALTS.  [CHAP.  n. 

pery,  and  can  be  laid  in  a  monoltihic  sheet  without  joints,  which 
cannot  be  said  of  artifical  stone.  It  is  particularly  recommended 
for  breweries,  paper  mills,  pulp  mills,  laundries  and  other  floor  sur- 
faces, which  from  the  nature  of  the  business  are  frequently  wet  and 
covered  with  water.  It  will  not  rot;  it  has  no  joints;  no  water 
can  leak  through  to  damage  ceilings  or  goods  stored  in  lower  floors. 

Under  usual  circumstances  one  inch  of  asphalt  mastic  will 
stand  any  ordinary  traffic.  In  exceptional  cases,  however,  such  as 
in  wash  houses  and  racking  cellars  of  breweries,  a  thickness  of  one 
and  a  half  to  two  inches  is  advisable. 

For  cellars  and  floors  for  light  business  purposes  three- 
quarters  of  an  inch  will  suffice. 

Asphalt  floors  are  preferably  laid  on  concrete  three  inches  thick, 
or  in  case  of  fireproof  construction  of  hollow  brick  arches  concrete 
leveled  off  about  half  an  inch  above  the  iron  beams.  Still,  asphalt 
can  be  laid  with  advantage  on  wooden  floors,  in  which  case  felt 
paper  is  laid  on  the  boards  to  prevent  any  trouble  from  warping  of 
the  wood.  One  of  the  largest  fields  for  the  use  of  asphalt  coule  is 
for  park  walks.  For  nearly  a  quarter  of  a  century  the  Park  De- 
partment of  New  York  has  used  this  description  of  pavement,  and 
with  the  exception  of  Madison  Square,  every  park  from  the  Battery 
to  St.  Mary's,  in  the  Bronx,  has  had  almost  its  entire  walk  areas 
finished  with  an  asphalt  surface. 

In  view  of  the  satisfaction  that  this  work  has  given,  it  may  be 
well  to  give  the  specification  prepared  by  the  department  engineer, 
who,  after  calling  for  a  foundation  of  three  inches  of  Portland 
cement  concrete,  says: 

"After  the  base  has  been  prepared  as  specified,  and  with  its  sur- 
face clean  and  dry,  a  layer  of  Seyssel  or  Mons,  Neuchatel,  Sicilian 
or  Limmer  asphalt  mastic,  in  no  place  less  than  one  inch  in  thick- 
ness, after  having  received  its  ultimate  compression,  is  to  be  placed 
upon  the  base,  carefully  and  evenly  compressed  with  the  proper 
tools  for  that  purpose,  and  the  finished  surface  to  be  free  from  de- 
pressions and  truly  and  evenly  surfaced  to  the  finished  grades  and 
crown  of  the  walk.  The  asphalt  mastic  to  consist  of  natural  bitu- 
minous limestone  rock  (i)  from  the  French  mines  of  Seyssel  or 
Mons,  equal  in  quality  and  composition  to  that  mined  by  the  Com- 
pagnie  Generate  des  Asphalte  de  France;  (2)  from  the  Swiss  mines 
at  Val  de  Travers,  equally  in  quality  and  composition  to  that  mined 
by  the  Neuchatel  Asphalt  Co.,  Ltd.;  or  (3)  from  the  Sicilian  mines 


ROCK  ASPHALT  MASTIC.  19 

at  Ragusa  and  the  German  mines  at  Limmer,  equal  in  quality  and 
composition  to  that  mined  by  the  United  Limmer  and  Vorwohle 
Rock  Asphalt  Co.,  Ltd.,  mixed  with  fine,  clean  grit  and  refined  bitu- 
men, in  such  proportions  and  in  such  manner  as  to  insure  work  that 
shall  be  sound  and  free  from  cracks  and  impervious  to  moisture 
under  all  climatic  changes,  and  so  as  not  to  flow  or  spread  in  sum- 
mer or  crack  or  disintegrate  in  winter,  and  as  shall  be  directed  by 
and  to  the  satisfaction  of  the  engineer." 

Rock  asphalt  coule  has  been  used  for  many  other  purposes 
than  in  building  and  for  sidewalks.  The  latest  use  I  have  seen 
was  for  medallion  plaques.  Among  the  larger  calls  for  this  ma- 
terial is  that  for  reservoir  linings.  Municipal  Engineering  in  one 
of  its  issues  describes  the  construction  of  one  in  Astoria,  Ore., 
where  the  bottom  was  covered  with  6  inches  of  concrete 
containing  0.9  cu.  yd.  of  crushed  rock,  0.5  cu.  yd.  of  gravel,  o.i 
cu.  yd.  of  sand  and  one  barrel  of  Portland  cement  per  cu.  yd.  cut 
in  blocks  of  20  ft.  square,  with  ^2-inch  asphalt  joints,  and  this  was 
covered  with  a  ^-inch  cement  mortar  finish  and  two  coats  of 
asphalt,  one  soft  and  the  other  harder,  and  together  a  little  more 
than  one  inch  thick.  The  slope  had  6  inches  concrete,  2-3-inch 
asphalt,  a  layer  of  brick  and  a  second  layer  of  asphalt  0.5  inch 
thick.  The  most  common  practice  is  probably  from  18  to  24 
inches  of  clay  puddle  under  concrete  or  paving. 

One  of  the  large  pieces  of  work  in  this  line  was  the  coating 
of  the  Queen  Lane  Reservoir,  Philadelphia,  where  an  area  of 
235,000  square  yards  was  surfaced  in  1896  under  the  direction  of 
Mr.  John  C.  Trautwine,  C.  E.  In  1897  tne  reservoir  at  Coates- 
ville,  Pa.,  with  a  capacity  of  2,000,000  gallons  of  water,  was  aban- 
doned on  account  of  excessive  leakage,  but  having  been  lined  with 
Neuchatel  coule  in  that  year,  has  been  in  use  and  given  perfect 
satisfaction  ever  since ;  this  work  was  done  under  the  direction  of 
Mr.  Alexander  Potter,  C.  E.,  of  New  York,  who  also  had  the 
Phoenixville,  Pa.,  reservoir  lined  with  Seyessel  asphalt  in  the  year 
1898. 

In  connection  with  asphalt  coule  a  desirable  combination  of 
iron  with  asphalt  has  lately  come  into  use.  This  construction  has 
been  adopted  by  the  Fire  Department  of  New  York  for  stalls  in 
engine  houses ;  it  has  been  used  for  the  space  inside  street  railroad 
tracks  and  one  foot  on  the  outside.  The  pavement  consists  of  cast- 
iron  frames  or  gratings  embedded  in  asphalt.  The  frame  prevents 


20  ASPHALTS.  [CHAP.  n. 

the  asphalt  from  creeping  and  from  wearing  into  holes  or  grooves. 
The  frame  is  cast  in  the  form  of  curved  or  undulating  bars  and 
crossbars,  with  stubs  at  the  point  of  intersection.  These  frames 
are  entirely  embedded  in  asphalt,  presenting  a  plain  asphalt  sur- 
face as  in  any  ordinary  pavement.  Even  under  heavy  traffic  the 
asphalt  wears  down  only  to  the  stubs.  Even  when  worn  the  sur- 
face shows  a  minimum  of  iron  and  a  maximum  of  asphalt  surface. 
When  by  such  wear  the  stubs  become  exposed,  the  best  course  is, 
by  the  use  of  surface  heater, .to  lay  asphalt  about  half  an  inch  in 
thickness  upon  the  surface,  which  makes  the  pavement  as  good  as 
new.  At  all  times  the  presence  of  the  iron  frame  prevents  the 
forming  of  ruts  or  grooves,  even  under  the  influence  of  summer 
heat  and  heavy  traffic,  and  the  laying  of  a  new  asphalt  coating 
upon  worn  pavements  may  be  postponed  for  a  considerable  period 
after  the  iron  stubs  are  exposed,  and  until  a  convenient  time  for 
making  the  repairs,  the  frame  in  the  meantime  preventing  the 
destruction  of  the  pavement  by  wear. 

This  device  is  protected  by  patents.  In  connection  with  pat- 
ents it  is  interesting  to  note  that  the  first  patent  in  connection 
with  asphalt  was  taken  out  by  Admiral,  the  Earl  of  Dundonald,  in 
1851,  for  the  employment  of  Trinidad  asphalt  and  mineral  bitumen 
of  the  North  American  Colonies  in  the  production  of  artificial 
stones  and  other  useful  objects.  He  acquired  land  in  La  Brea, 
Island  of  Trinidad,  which  still  remains  in  the  hands  of  his  family, 
and  the  Dundonald  property  is  today  contributing  material  for  our 
city  streets. 

Other  English  patents  include  Pym's  composition,  patented 
in  1855,  which  was  composed  of  5  cwt.  of  asphalt,  5  cwt.  of  chalk 
or  limestone,  I  Ib.  of  sal  ammoniac,  and  as  much  coarse  sand  and 
grit  as  will  mix  freely  with  the  above  ingredients  when  heated  in 
a  cauldron;  the  heated  mixture  is  then  cast  into  the  desired  forms, 
and  if  extra  toughness  is  required,  cocoanut  fiber,  shavings,  or 
other  fibrous  materials  must  be  well  incorporated. 

In  RowclifFs  patent  (1855,  pt.  2,  906),  the  asphalt  is  reduced 
to  small  particles,  and  compressed  by  hydraulic  or  other  pressure 
into  the  desired  shapes;  sand  or  powdered  stone  may,  if  necessary, 
be  added  to  it  before  compression. 

Sheil's  stone,  patented  in  1867,  consisted  of  small  stone  ce- 
mented together  with  asphalt. 

R.  Skinner's  patented  asphalt  blocks  are  prepared  as  follows: 


'A  S  P  H  A  L  TS' 


ROCK  ASPHALT  MASTIC.  21 

800  Ibs.  of  asphalt  are  placed  in  an  oven  and  submitted  to  sufficient 
heat  to  drive  off  water  and  easily  volatized  matters.  In  a  short 
time  the  material  is  capable  of  being  easily  powdered,  and  in  this 
state  it  is  introduced  into  a  large  revolving  cylinder  heated  up  to 
200  degrees  Fahr.,  and  then  are  added  300  Ibs.  each  of  pulverized 
slag,  coke,  and  limestone,  and  about  20  gallons  of  mineral  tar. 
The  tar  should  be  previously  boiled  to  expel  water,  and  thoroughly 
mixed  with  limestone  before  being  added  to  the  other  ingredients. 
After  mixing  and  heating,  the  product  is  conducted  from  the  re- 
volving cylinder  to  a  revolving  pan  and  the  temperature  lowered 
to  150  degrees  Fahr.;  in  this  state  it  is  placed  in  molds  and  sub- 
jected to  heavy  pressure. 

Tucker,  an  American  patentee,  also  compressed  mixtures  of 
slag  and  asphalt  into  blocks. 

Fottrel's  patent  in  1873,  pat.  3,086,  prepares  an  artificial  stone 
especially  adapted  for  making  drains,  pipes,  etc.,  by  boiling  to- 
gether a  mixture  of  13  cwt.  of  finely  powdered  stone,  4  gallons  of 
shale  oil,  2  cwt.  Trinidad  asphalt,  and  2  cwt.  bituminous  rock. 
When  thoroughly  mixed,  the  composition  is  run  into  suitable 
molds. 

M.  Leon  Malo  patented  in  France  in  1873  his  asphalt  corn- 
prime  blocks  which  have  so  long  been  in  use  in  that  country  and 
which  recently  have  been  in  great  demand  in  Cairo,  Egypt. 

Wilkinson's  patent  Trinidad  asphalt  blocks,  generally  known 
as  the  "Hasting"  blocks,  seem  up  to  the  present  to  have  had  the 
monopoly  of  such  construction  in  this  country  and  South  America. 

For  quite  a  number  of  years  these  blocks  were  made  of  lime- 
stone, but  in  1893  trap-rock  was  substituted  for  the  limestone. 
Blocks  made  of  this  latter  material  give  much  better  satisfaction 
on  account  of  the  greater  durability  of  the  trap-rock,  and  at  the 
present  time  that  material  is  being  used  entirely  in  the  manufac- 
ture of  the  blocks.  Asphaltic  cement  is  mixed  with  the  trap-rock 
in  proper  proportions  at  a  temperature  of  about  300  degrees.  The 
material  is  placed  in  a  press  at  this  temperature  and  each  block  is 
subjected  to  a  pressure  of  120  tons.  After  leaving  the  press  the 
blocks  are  gradually  cooled  in  a  water  bath,  and  are  then  ready 
for  use. 

In  the  earlier  years  of  the  industry  blocks  were  made  4  x  5  x  12 
inches.  A  depth  of  5  inches,  however,  was  considered  to  be  un- 
necessary, and  the  present  practice  makes  them  of  the  same  dimen- 


22  ASPHALTS.  [CHAP.  n. 

sions  as  above,  except  that  the  depth  is  4  and  3  inches,  the  blocks 
weighing  13^  and  18  Ibs.,  respectively.  These  blocks  are  carried 
to  the  streets  and  laid  upon  a  base  of  either  gravel,  broken  stone, 
or  concrete,  as  the  case  may  be.  The  blocks  are  laid  in  practically 
the  same  manner  as  are  bricks,  the  joints  being  filled  with  fine 
sand. 

Another  form  of  asphalt  blocks,  known  as  the  "Jenner"  pat- 
ent, is  sometimes  used,  in  which  the  broken  stone  is  replaced  by 
granulated  cork.  Such  blocks  were  laid  on  Fifth  Avenue,  New 
York,  between  Thirty- fourth  and  Thirty-sixth  streets,  in  strips  ten 
feet  wide,  adjacent  to  the  curb.  The  grade  on  these  two  blocks 
being  somewhat  steeper  than  the  remainder  of  the  avenue,  it  was 
deemed  best  to  provide  a  better  foothold  for  horses  in  slippery 
weather  than  the  ordinary  asphalt.  The  blocks  are  2  x  4^  x  9 
inches,  and  were  set  flatwise. 

The  courtyard  of  the  Waldorf-Astoria  was  afterward  laid 
with  such  blocks.  This  pavement  was  laid  in  the  fall  of  1897,  and 
in  the  spring  of  1900  was  in  very  good  condition.  It  cost  $5.25 
per  square  yard,  exclusive  of  foundation,  under  a  fifteen-year 
guarantee.  Although  very  desirable  for  driveways  and  bridges, 
cork  blocks  can  never  be  very  generally  used  on  account  of  their 
excessive  cost. 

The  question  of  patents  has  taken  me  from  the  subject  of 
asphalts  mastics  to  which  I  must  return.  For  sidewalks  or  iron 
bridges  asphalt  coule  is  often  used  where  the  roadway  is  of  asphalt 
pitch  composition,  or,  as  is  known,  the  "Standard  American  Pave- 
ment," as  being  subject  only  to  footwear  on  the  top  surface — need 
only  be  laid  one  inch  thick,  and  here,  as  in  other  cases,  where 
heavy  steam  rollers  cannot  well  be  used  for  compression,  the  mastic 
is  preferable,  as  it  is  so  solid  when  poured  on  the  surface  to  be 
covered  that  it  needs  only  a  slight  pressure  from  the  workman 
spreading  it  to  the  required  grade. 

The  American  rock  asphalts  have  not  proved  satisfactory  for 
the  manufacture  of  mastic;  this  is  from  the  fact  that  they  are 
generally  of  sand-rock  and  not  lime-rock  formation.  A  company 
in  St.  Louis  tried  the  experiment  of  making  a  mastic  from  the 
Indian  Territory  asphalt  sandstones,  but  I  understand  abandoned 
its  use  for  that  of  European  rock  mastic.  Another  Western  firm 
tried  the  use  of  Kentucky  asphalt  sandstone,  but  also  changed  to 
limestone.  The  single  exception,  I  personally  know  of,  is  found  in 


ROCK  ASPHALT  MASTIC.  23 

the  Texas  rock  asphalt  mixed  near  Cline,  in  Uvalde  Co.,  which  is 
a  genuine  asphalt  limestone.  I  visited  these  mines  in  the  spring  of 
1901  and  was  much  interested  in  the  formation,  which  was  shell 
limestone  richly  impregnated  with  bitumen,  the  average  analysis 
showing  16  per  cent,  of  bitumen  with  streaks  much  richer.  I 
obtained  very  fine  specimens  of  fossils  showing  different  kinds  of 
shells  and  proving  that  the  mine  had  originally  been  under  the 
ocean.  This  rock  having  been  reduced  to  a  powder  is  rich  enough 
to  be  cooked  into  a  mastic  without  the  addition  of  bitumen,  a  small 
percentage  of  maltha,  however,  is  desirable  to  cause  it  to  flow 
readily  into  molds.  At  San  Antonio  a  large  stable  in  the  rear  of 
the  "Menger"  Hotel  has  a  floor  laid  some  years  ago  with  this 
material  which  has  stood  the  test  of  hard  usage  even  better  than 
the  average  European  mastic.  It  has  been  laid  also  in  Houston, 
Texas,  to  a  considerable  extent,  but  the  heavy  cost  of  freight 
prohibits  its  use  in  the  East;  New  Orleans,  however,  may  prove 
a  favorable  point  for  its  use. 


CHAPTER  III. 
TRINIDAD  ASPHALT. 


TRINIDAD  asphalt  is  the  bitumen  best  known  in  the  United 
States,  and  its  use  for  street  pavement  has  been  colossal. 
This  asphalt  was  first  used  as  a  substitute  and  improvement  on  coal 
tar  for  roofing  and  like  purposes,  and  succeeded  the  coal  tar  pave- 
ments first  brought  into  prominence  in  the  "Tweed  Ring"  days. 

In  1870  Professor  E.  J.  De  Smedt,  a  Belgian  chemist,  laid 
what  is  believed  to  have  been  the  first  sheet  asphalt  pavement  in 
this  country  in  front  of  the  City  Hall  in  Newark,  N.  J.  His  Euro- 
pean knowledge  led  him  to  endeavor  to  make  an  artificial  bitumin- 
ous mixture  on  the  line,  as  far  as  possible,  of  the  natural  rock 
asphalt  powder  used  in  Paris. 

In  1873,  Fifth  Avenue,  New  York,  opposite  the  Worth  Monu- 
ment, was  laid  with  this  composition  which  was  described  as  a 
mixture  of  properly  selected  sand  and  pulverized  carbonate  of 
lime  cemented  together  by  suitable  asphalt,  the  latter  being  first 
refined  and  tempered  with  heavy  petroleum  oils  or  residuum. 

From  these  beginnings  have  evolved  the  immense  industry 
of  the  "Standard  Asphalt  Pavement,"  of  which  to-day,  there  are 
forty  million  square  yards  in  the  United  States,  and  of  this  quantity 
it  is  claimed  85  per  cent,  is  of  a  mixture  in  which  Trinidad  asphalt 
is  used. 

Municipalities  and  engineers  have  been  greatly  exercised  over 
the  question  of  the  supposed  difference  in  asphalt  refined  from 
the  Pitch  Lake  and  from  adjoining  properties.  The  writer  has 
always  maintained  that  there  was  no  difference  in  the  qualities  and 
this  is  now  the  generally  accepted  decision  of  army  engineer  offi- 
cers and  city  engineers. 

The  deposit  of  the  Pitch  Lake,  as  described  by  Mr.  P.  W. 
Henry,  general  manager  of  the  Barber  Asphalt  Paving  Co.,  occu- 
pies a  bowl-like  depression,  probably  the  center  of  an  extinct  mud 
volcano,  some  of  which  are  found  in  other  parts  of  the  island. 


'A  S  P  H  A  L  T  S' 


TRINIDAD   ASPHALT.  25 

The  center  of  the  deposit  is  about  three-quarters  of  a  mile  from 
the  shores  of  the  Gulf  of  Paria,  and  about  135  feet  above  the  level 
of  the  sea,  making  it  easier  of  access  and  simplifying  the  question 
of  shipment.  The  surface  is  hard  enough,  except  in  irregular 
patches  in  the  center,  to  bear  the  weight  of  carts  and  mules.  It  is 
necessary,  however,  for  one  to  keep  moving,  otherwise  he  soon 
sinks  in  the  material  which,  under  the  hot  rays  of  the  sun  becomes 
quite  mobile,  although  not  sticky,  owing  to  the  large  amount  of 
water  which  it  contains.  The  surface  of  the  deposit  is  divided  into 
irregular  areas,  from  60  to  150  feet  in  diameter,  separated  by 
crevices  several  feet  across  and  from  six  inches  to  six  feet  or  more 
in  depth,  in  which  rain  water  collects  and  in  which  fishes,  some  six 
inches  long,  resembling  mullets,  disport  themselves.  Each  of  these 
areas  has  a  motion  of  its  own  from  the  center  to  the  edge,  due  to 
the  gas  which  is  being  evolved.  If  a  stake  is  placed  in  the  center 
of  one  of  these  areas  it  will  gradually  work  to  the  edge  and  finally 
disappear.  The  crevices  are  found  where  the  different  areas  meet, 
and  although  the  edges  of  the  asphalt  in  these  areas  touch  each 
other  at  a  greater  or  less  depth,  they  do  not  appear  to  unite. 

This  deposit  has  well  been  called  a  lake,  and  it  possesses  the 
qualifications  which  such  a  name  would  imply.  It  occupies  limits 
well  defined  by  shores.  From  borings  made  it  appears  that  the 
deposit  occupies  a  bowl-shaped  basin,  the  bottom  of  which  100  feet 
from  the  shore  is  about  90  feet  from  the  surface.  The  depth  in 
the  center  is  unknown  as  it  was  impossible  with  the  implements 
employed  to  bore  to  a  depth  greater  than  135  feet,  through  all  of 
which  the  material  was  similar  to  that  on  the  surface. 

When  asphalt  is  dug  from  any  portion  of  the  deposit,  in  the 
course  of  a  few  days  the  hole  is  filled  by  new  material  coming  from 
below,  but  the  entire  area  of  the  lake,  114  acres,  is  lowered  in  con- 
sequence, showing  that  the  mass  acts  as  a  liquid  of  less  mobility, 
however,  than  water. 

The  composition  of  the  asphalt  is  of  remarkable  uniformity, 
no  matter  from  which  portion  of  the  lake  it  is  taken.  Sam- 
ples taken  135  feet  deep  at  the  center  did  not  differ  in  composition 
from  those  taken  on  the  surface  a  few  feet  from  the  shore,  show- 
ing the  homogeneousness  of  the  entire  mass.  Then,  too,  the  sur- 
face is  in  constant  motion.  There  are  on  the  surface  of  the  lake 
half  a  dozen  or  more  islands,  from  50  to  150  feet  in  diameter,  com- 
posed of  floating  vegetation,  with  trees  thirty  to  forty  feet  high 


26  ASPHALTS.  [CHAP.  in. 

and  dense  undergrowth.  From  accurate  surveys  it  was  found  that 
one  of  these  islands  in  one  year  moved  over  25  feet.  There  are 
also  more  rapid  movements  corresponding  to  currents  and  eddies 
in  a  lake.  In  making  surveys  for  the  tramway,  different  lines 
were  run  across  the  lake  and  stakes  put  in  every  100  feet.  These 
stakes  were  put  in  line  with  a  transit,  and  the  following  day  the 
alignment  was  about  the  worst  possible.  In  20  days  one"  of  the 
stakes  had  moved  24  feet,  or  over  a  foot  per  day,  and  other  stakes 
from  that  amount  down  to  a  few  feet. 

This  motion  is  due  to  the' evolution  of  gas  which  is  constantly 
being  given  off,  and  in  some  places  in  such  quantities  that  it  can  be 
ignited  by  a  match.  Then,  too,  the  lake  is  fed  by  springs  bringing 
in  new  material  to  the  amount  of  at  least  10,000  tons  per  year. 
Near  the  center  of  the  lake  this  soft  asphalt  appears  and  spreads 
over  the  old  and  hardened  surface.  The  lighter  oils  evaporate 
under  the  rays  of  the  tropical  sun  and  the  new  material  then  be- 
comes hardened  like  the  rest  of  the  lake. 

The  resemblance  of  this  deposit  to  a  lake  may  therefore  be 
summed  up  as  follows :  Its  occurrence  in  a  basin  with  well  defined 
shores  and  bottom;  its  movement  as  a  mass,  preserving  its  level; 
the  uniformity  of  its  composition ;  the  movement  of  its  surface ;  the 
presence  of  islands  and  the  existence  of  springs. 

From  levels  taken  by  Mr.  Henry  in  February,  1893,  and  again 
a  year  later,  it  appears  that  the  center  of  the  lake  is  almost  a  foot 
higher  than  the  edges.  This  is  probably  due  to  the  ebullition  of 
the  soft  asphalt  near  the  center.  Levels  have  been  taken  every 
year  since  that  date,  and  it  appears  that  the  lake  preserves  its  con- 
tour, although  the  general  level  has  been  lowered  nearly  four  feet 
in  the  past  eight  years.  It  has  been  found  that  the  removal  of 
about  18,000  tons  of  asphalt  will  lower  the  level  one  inch,  and  as 
the  output  is  about  100,000  tons  per  year,  the  level  is  lowered  from 
five  to  six  inches  per  year. 

From  the  borings,  however,  it  is  evident  that  for  several  gen- 
erations to  come  there  will  be  no  shortage.  These  borings  were 
made  with  the  ordinary  portable  water- jet  machine,  such  as  is  used 
in  making  borings  through  sandy  material,  and  it  was  well  suited 
for  the  purpose.  It  took  several  days  to  make  the  borings  in  the 
center  of  the  lake,  and  by  that  time  the  casing  had  gotten  so  far 
out  of  plumb,  due  to  the  motion  of  the  asphalt,  that  it  was  impos- 
sible to  drive  it  any  deeper.  This  casing  finally  disappeared, 


TRINIDAD   ASPHALT.  27 

although  its  top  originally  stood  six  or  eight  feet  above  the 
surface. 

The  asphalt  is  dug  by  means  of  picks  or  mattocks  just  before 
da\y,n,  when  the  asphalt  is  comparatively  brittle,  and  in  the  early 
days  of  the  industry  was  loaded  upon  carts  and  taken  to  the  beach, 
where  it  was  stored  until  the  arrival  of  vessels,  or  dumped  directly 
into  lighters  which  carried  it  to  the  sailing  vessels  or  steamers 
anchored  half  a  mile  out  from  shore. 

As  the  business  increased  it  became  necessary  to  install  more 
rapid  and  economical  methods  of  loading.  Surveys  for  the  tram- 
way and  pier  were  made  in  February,  1893,  by  Mr.  Henry,  who 
outlined  the  plan  finally  adopted.  Detailed  plans  and  specifications 
were  made  by  L.  L.  Buck,  C.  E.,  and  the  resident  engineer  in 
charge  of  erection  was  E.  G.  Freeman,  C.  E.,  and  it  was  finished  in 
the  fall  of  1894. 

In  consequence  of  disputes  and  claims  of  inferiority  of  the 
so-called  "Land  Asphalt,"  Professor  S.  F.  Peckham,  in  1895,  vis- 
ited Trinidad,,  and  as  the  result  of  his  investigations  reported  that 
he  was  "quite  at  a  loss  to  determine  why  Mr.  Richardson  alleges 
such  a  specific  distinction  between  what  he  is  pleased  to  term  'lake' 
and  'land'  asphalt.  It  appears  to  me  to  be  a  distinction  without  a 
difference." 

Professor  Peckham  states  that  it  is  evident  that  for  an  indefi- 
nite period  there  has  been  an  outflow  of  bitument  from  the  lake 
towards  the  sea,  at  La  Brea,  not  over  its  rim,  but  through  a  crevice 
in  its  side;  in  fact,  through  its  broken-down  side;  and  that,  not- 
withstanding the  vast  quantities  of  asphalt  now  being  taken  from 
the  lake  by  the  concessionaires,  the  movement  is  still  out  of  .the 
lake.  Captain  Alexander,  in  1832,  spoke  of  the  flow  out  of  the  lake 
as  "immense."  Manross,  in  1855,  says:  "This  stream  of  pitch 
has  been  dug  through  in  several  places,  averaging  from  15  to  18 
feet  in  depth.  A  well  dug  at  one  point  on  the  slope  of  the  over- 
flow, was  abandoned  still  showing  asphalt,  at  the  depth  of  forty 
feet.  Several  village  lots  have  ben  excavated  to  a  depth  of  twenty 
feet  still  in  asphalt.  The  invariable  reply  of  the  negroes  to  the 
question:  "Have  you  ever  dug  through  the  asphalt?"  was,  "No, 
sir."  The  conclusion  that  Professor  Peckham  reached  on  the 
ground  was,  that  the  asphalt  flowing  down  the  slope  to  the  sea 
fills  a  ravine  excavated  by  water,  and  that  it  is  slowly  moving  out 
of  the  lake  with  the  pressure  of  the  asphalt  in  the  lake  behind  it. 


28  ASPHALTS.  [CHAP.  m. 

This  conclusion  is  in  harmony  with  the  testimony  of  observers 
for  the  last  hundred  years.  It  is  from  one  of  such  overflow  de- 
posits in  the  village  of  La  Brea  that  the  asphalt  from  the  Countess 
Dundonald's  property  is  obtained.  The  Roman  Catholic  Church 
property  also  has  reduced  large  quantities  of  asphalt  which  has 
allowed  of  the  competition  in  asphalt  pavement  work,  which  was 
so  prominent  a  feature  during  1899  to  1902. 

For  paving  purposes  refined  Trinidad  asphalt  of  itself  is  too 
hard  and  brittle  to  form  the  cementing  agent  to  bind  the  particles 
of  sand  together.  It  is  therefore  necessary  to  use  a  flux  to  bring 
the  asphalt  to  the  proper  consistency.  For  this  purpose  petroleum 
residuum  has  been  generally  used,  although  liquid  asphalts  from 
California  have  been  used  to  some  extent  and  with  more  satisfac- 
tion. 

As  liquid  asphalt  is  more  expensive  and  residuum  has  been 
used  for  many  years  with  fair  results,  it  has  been  the  fluxing  agent 
in  general  use.  Professor  Samuel  P.  Stadler,  after  exhaustive 
tests  gave  the  opinion  that  oil  residuum  should  not  be  used,  and 
that  maltha,  of  the  nature  of  the  California  liquid  asphalt,  was  the 
best  flux. 


- 


"A  S  P  H  A  L  T  S' 


CHAPTER  IV. 

PETROLEUM  RESIDUUM  AND  CALIFORNIA  MALTHAS 
AS  A  FLUXING  MATERIAL. 


REFERRING  to  the  use  of  petroleum  residuum  as  a  fluxing 
material,  this  residuum  is  a  heavy,  dark  oil,  resembling  the 
cheaper  lubricating  oils,  and  contains  none  of  the  lighter  oils.  Its 
gravity  is  from  20  degrees  to  22  degrees  Beaume,  flash  point  about 
450  degrees  F.,  quick  flow  at  78  degrees  F.,  and  containing  only  a 
few  per  cent,  of  volatile  matter  in  seven  hours  at  400  degrees  F. 

In  order  to  make  a  satisfactory  asphalt  cement  (as  the  mix- 
ture of  refined  asphalt  and  residuum  is  called),  it  is  customary  to 
mix  it  in  the  proportion  of  about  100  parts  of  refined  asphalt  to  20 
parts  of  residuum.  The  asphalt  is  first  melted  in  tanks  and  the 
residuum  is  then  added  and  thoroughly  mixed  by  agitating  with 
air  or  steam.  As  the  quality  of  the  residuum  varies,  it  is  not  pos- 
sible to  gauge  the  exact  amount  necessary  by  weight.  Samples 
are  therefore  taken  by  the  foreman  in  charge  and  tested  by  chew- 
ing. By  practice  a  man  can  become  expert  in  this  line,  but  it  is  of 
course  necessary  to  have  a  standard  sample  for  comparison.  At 
the  laboratory  and  at  the  larger  plants  the  consistency  of  the 
asphalt  cement  is  tested  by  an  apparatus  called  the  penetration 
machine,  and  the  consistency  of  the  cement  is  recorded.  Other 
methods  for  determining  the  consistency  are  also  in  use,  and  each 
has  its  merits.  For  quick  service  the  chewing  test  is  as  accurate 
as  any  other,  but  there  is  no  method  of  recording  its  results.  The 
asphalt  cement,  which  in  the  tanks  is  carried  at  a  temperature  of 
300  degrees  to  350  degrees  F.,  is  now  ready  for  use,  and  is  added 
to  the  hot  sand  and  other  mineral  matter  in  a  mixer  which  is  simply 
a  box  encasing  two  shafts  revolving  in  opposite  directions,  on- 
which  are  blades  shaped  like  propeller  blades.  The  mixture  is  gen- 
erally made  in  batches  of  nine  cubic  feet,  and  the  time  of  mixing 
is  from  a  minute  to  a  minute  and  a  half.  The  resultant  mixture  is 


30  ASPHALTS.  [CHAP.  iv. 

then  dumped  into  wagans,  hauled  to  the  street,  raked  and  rolled 
with  a  steam  roller,  and  the  asphalt  pavement  after  a  few  hours 
cooling,  is  then  ready  for  traffic. 

In  1894  the  Citizens  Municipal  Association  and  Trades 
League  of  Philadelphia  employed  Professor  Samuel  P.  Stadler  and 
Mr.  J.  Edward  Whitfield  to  investigate  the  properties  of  the  dif- 
ferent fluxing  materials  and  they  reported  that  "better,  stronger 
and  in  all  probability  more  durable  paving  composition  can  be 
made  than  those  now  being  made  with  the  aid  of  oil  residuum." 
This  decision  was  based  on  exhaustive  tests  of  Trinidad  with  Cali- 
fornia and  Utah  Malthas. 

The  general  deduction  was  that  the  blending  of  the  asphalt 
and  the  oil-residuum  is  an  unsatisfactory  one  on  the  score  of  its 
lack  of  durability,  and  I  have  since  found  from  conversation  with 
practical  men  of  many  years'  experience  in  asphalt  paving  that 
such  is  the  common  belief.  It  is  also  admitted  by  the  chief  writers 
on  the  subject  of  asphalt  paving  that  the  quality  of  an  asphalt  is 
reduced  in  the  ratio  of  the  percentage  of  increase  of  petroleum  oil 
used. 

There  are  two  methods  as  stated  by  Messrs.  Stadler  and 
Whitfield  by  which  the  use  of  petroleum  residuum  in  asphalt 
paving  mixtures  can  be  done  away  with ;  the  first  is  to  find  natural 
asphalts  which  retain  sufficient  of  their  original  asphaltic  oils  to 
make  it  possible  to  use  them  with  no  other  admixture  than  the 
proper  amounts  of  sand  and  pulverized  limestone,  the  other  is  to 
mix  with  the  hard  natural  asphalts,  liquid  natural  asphalts,  of 
which  a  number  are  found  on  the  Pacific  Coast,  and  in  Utah, 
Idaho,  Montana  and  elsewhere  in  the  West. 

The  second  method  of  making  a  paving  composition  which 
shall  do  away  with  the  necessity  for  the  use  of  the  oil  residuum  is 
to  flux  the  solid  asphalt  with  the  natural  liquid  asphalt.  This  has 
been  done  already  in  California  with  excellent  results. 

As  no  figures  had  then  been  published  by  which  one  could 
judge  of  the  reliability  of  these  claims,  it  was  determined  to  make 
a  study  of  the  paving  compositions  that  could  be  made  with  the 
liquid  asphalts  used  as  tempering  material  for  the  solid  asphalts. 
They  therefore  procured  a  quantity  of  California  liquid  asphalt  and 
a  specimen  of  liquid  asphalt  from  Utah.  In  order  to  have  a  clear 
understanding  of  the  nature  of  these  materials  and  how  their  addi- 
tion would  effect  the  composition  of  the  finished  mixture,  it  was 


PETROLEUM   RESIDUUM.  31 

thought  desiraWe  to  make  a  partial  chemical  analysis  of  them,  de- 
termining the  amount  of  bitumen  contained  and  its  quality. 

These  analyses  showed:  California  maltha  98.70  per  cent,  of 
bitumen,  and  in  the  Utah  76.15  per  cent,  of  bitumen,  both  soluble 
in  carbon  disulphide. 

California  asphalts  in  forms  of  Maltha  Brea,  and  Stone  or 
Rock  asphalt  are  found  in  abundance  in  the  Southern  and  South- 
ern Central  counties  of  the  State.  They  were  known  to  and  used 
by  the  native  Indians  for  making  their  canoes  watertight,  and 
in  some  measure  as  a  mortar  for  cementing  together  the  stones 
of  their  rude  buildings,  unconsciously  following  the  practice  of  the 
Babylonians  more  than  4,000  years  ago. 

As  Maltha,  the  bitumen  oozes  from  orifices  in  the  earth, 
called  locally  "Tar  Springs." 

At  Brea,  this  exuded  Maltha  lies  in  blanket  form,  usually  in 
thin  masses  but  sometimes  in  deep  bodies  rilling  up  holes,  chasms 
and  ravines.  Under  the  action  of  the  sun's  heat  the  soft  Maltha 
has  slowly  thrown  off  its  volatile  elements,  which  with  the  action 
of  the  oxygen  of  the  atmosphere  has  produced  a  more  or  less  hard 
and  brittle  asphalt,  more  or  less  pure  or  mixed  with  earthy  matter. 

As  Stone  or  Rock  asphalt  it  is  found  in  many  places  in  regu- 
lar, true  fissure  vein  formation  of  very  old  geological  age,  the  vola- 
tiles  nearly  eliminated  from  gases  and  from  the  rocks  and  earth 
surrounding  and  covering  it. 

The  Maltha,  as  issuing  from  the  Tar  Springs  is  usually  very 
pure  in  bitumen. 

The  Brea  is  less  pure  and  very  variable,  according  as  it  gath- 
ered much  or  little  sand,  gravel  or  soil  in  its  progress  of  crawling 
under  the  sun's  heat. 

The  Rock  Asphalts  are  also  widely  variable  in  bituminous  pur- 
ity, according  to  the  amount  of  earthy  or  fossil  matter  intruding 
into  the  bitumen  while  still  viscous  or  even  at  its  earlier  stage  of 
fluidity  on  its  way  up  and  through  the  earth  fissures. 

In  one  or  other  of  these  forms  these  asphalts  have  been  in  use 
in  increasing  quantities  since  the  advent  of  Americans  in  Cali- 
fornia, most  largely  for  roofing,  next  for  paving  and  for  lining 
reservoirs  and  tanks,  and  to  a  large  extent  for  coating  water  pipe 
and  protecting  it  from  rust,  acid  and  alkalies. 

For  paving,  the  Rock  Asphalt  has  been  quite  largely  used  in 
the  Pacific  Ocean  States  and  Territories,  but  paving  material  made 


32  ASPHALTS.  [CHAP.  iv. 

from  Refined  Maltha  is  now  being  more  largely  employed  owing  to 
the  very  high  purity  of  the  bitumen,  enabling  shipment  to  far  dis- 
tant points  with  virtually  no  dead  matter  in  its  composition  to  pay 
freight  and  handling  on.  The  following  table,  giving  an  analysis 
of  a  common  type  of  these  Refined  Malthas,  will  illustrate  this : 

TABLE  III. 

REPINED    MALTHA    PAVING   CEMENT. 

Water  and  volatiles    09% 

Loss  at  212°  Fahrenheit: 

Total   bitumen 98.33% 

A*sh  (finely  divided  silicium) 1.58% 


100.00% 

Bitumen   composed   of  petrolene 75.15% 

Bitumen  composed  of  asphaltene 24.85% 

Specific  gravity  of  the  cement,   1,050. 

Considerable  quantities  have  been  shipped  to  states  east  of  the 
Rocky  Mountains,  and  the  increase  in  demand  has  shown  a  rapid 
growth  from  year  to  year.  Shipments  via  Panama  and  Cape  Horn 
to  Europe  are  increasing,  and  an  active  trade  is  beginning  with 
Asiatic  Pacific  countries.  A  recent  shipment  of  some  500  tons  on 
account  of  a  5,000  ton  order  has  been  made  to  Australia. 

Several  thousand  tons  are  used  annually  for  coating  wharf 
piles  which  the  asphalt  effectually  protects  against  Teredos  and 
Limnoriae. 

Some  ten  years  ago  a  civil  engineer  (Mr.  Templer  Tickell)  in 
employ  of  the  British  Government  at  Singapore  shipped  a  quantity 
of  refined  asphalt  from  California  and  applied  it  upon  the  timbers 
of  bridges,  docks  and  buildings  to  test  its  efficacy  in  resisting  the 
depredations  of  the  wood-eating  ants,  which  range  in  great  armies 
through  the  Straits  Settlement  and  attack  everything  of  wood, 
completely  consuming  heavy  timbers.  The  asphalt  resisted  them 
perfectly. 

Applied  to  metal  surfaces  which  in  the  very  hot  and  very 
humid  climate  of  Polynesia  corrode  to  an  extent  unknown  in  cooler 
and  drier  climates,  Mr.  Tickell  found  the  California  asphalts  a 
perfect  protection.  The  use  of  California  asphalts  for  street  pave- 
ments in  eastern  cities  is  growing  rapidly. 

Samples  of  them  were  recently  submitted  to  Professor  A.  W. 
Dow  by  a  Western  Asphalt  Company  and  resulted  in  the  following 
analysis  and  report: 


o  F 


o    > 
B   3 


*  K 
O    H 

td 
J»  ui 

*=3 

es 
IS 

o  * 
0  o 
»>  > 


"A  S  P  H  A  L  T  S' 


PETROLEUM   RESIDUUM.  33 

TABLE  IV. 
ANALYSIS  OF  CALIFORNIA  ASPHALT. 


(D) 

Hard.  (G) 

Bitumen.  Maltha. 

Total  bitumen  soluble  in  carbon  disulphide 99.10%  99.68% 

Organic  matter  not  bitumen 0.54%  0.12% 

Silica  and  clay   0.36%  0.20% 


100.00%     100.00% 

"None  of  the  samples  were  appreciably  altered  by  being  kept 
at  300  degrees  for  six  hours  in  an  open  vessel.  This  paving  ce- 
ment is  of  the  right  consistency  to  make  a  good  paving.  It  is 
adhesive  and  elastic.  It  is  not  brittle  at  a  low  temperature,  nor 
does  it  become  too  soft  at  a  high  atmospheric  temperature.  These 
samples  are  superior  to  any  I  have  ever  examined  in  physical  prop- 
erties, and  rank  among  the  better  asphalts  for  paving  purposes. 
Your  (D)  Asphalt  Paving  Cement,  by  combining  with  your  (G) 
Liquid  Asphalt  will  produce  a  most  splendid  article." 


CHAPTER  V. 
VENEZUELA  ASPHALT. 

VENEZUELA  asphalt  is  more  widely  known  to  the  public 
through  the  serious  -law  suits  which  have  almost  caused 
international  complications  than  from  its  actual  business  produc- 
tions, and  I  might  almost  say  that  Venezuela  is  about  as  prolific  in 
law  cases  as  in  bitumens,  but  there  are  certainly  large  deposits  of 
the  latter  throughout  the  republic. 

The  Bermudez  Lake,  which  up  to  the  present  has  really  been 
the  only  important  source  of  supply,  is  situated  across  the  Gulf  of 
Paria,  about  105  miles  due  west  of  the  Trinidad  Pitch  Lake,  in  the 
State  of  Bermudez,  Venezuela.  It  lies  in  a  straight  line  about  20 
miles  from  the  gulf,  but  by  the  San  Juan  and  Guanoco  Rivers  the 
distance  from  the  bar  at  the  mouth  of  the  river  is  some  40  miles. 

UTie  San  Juan  is  a  deep,  wide  river  and  although  there  are 
only  19  to  20  feet  of  water  at  the  bar,  in  the  river  itself,  the  water 
is  in  many  places  over  100  feet  deep.  From  the  San  Juan  branches 
a  smaller  river,  the  Guanoco,  and  three  miles  from  the  junction  is 
located  the  wharf  along  which  steamers  drawing  18  feet  of  water 
can  lie  and  receive  the  asphalt.  This  wharf  is  located  about  five 
miles  from  the  asphalt  lake,  to  which  it  is  joined  by  a  narrow- 
gauge  steam  railroad.  The  lake  covers  an  area  of  about  1,000 
acres,  being  nine  times  the  area  of  the  Trinidad  lake. 

This  larger  area  does  not  necessarily  indicate  a  larger  amount 
of  material  in  the  deposit,  for  the  asphalt  in  many  places  is  only  2 
to  10  feet  deep.  There  are  many  springs  of  soft  asphalt  or  maltha, 
the  largest  being  about  seven  acres  in  area.  Outside  of  the  springs 
where  new  material  is  constantly  exuding,  the  surface  of  the  lake 
is  covered  with  vegetation  and  trees,  which  must  first  be  cut  off 
to  reach  the  asphalt. 

The  quality  of  the  asphalt  varies  from  the  maltha,  or  liquid 
asphalt,  exuding  from  the  springs  to  the  hard  glance  pitch  which 
has  been  produced  by  fires  which  during  the  dry  season  sometimes 


VENEZUELA    ASPHALT.  35 

sweep  across  the  lake.  Underneath  the  roots  of  vegetation  is  the 
asphalt  of  commerce,  which  is  handled  in  much  the  same  way  as 
Trinidad,  although  it  is  considerably  softer. 

Its  composition  also  differs  considerably  from  that  of  Trini- 
dad, and  the  crude  material  does  not  present  the  uniformity  of 
Trinidad.  The  crude  Bermudez  asphalt  contains  water,  but  it  is 
present  as  a  mixture  and  not  as  an  emulsion.  In  percentage  the 
water  varies  from  10  to  4  per  cent.,  averaging  31  per  cent.,  whereas 
in  Trinidad  asphalt  the  quantity  is  constant  at  28  per  cent.  The 
mineral  matter  also  varies  from  less  than  I  per  cent,  to  more  than 
3  per  cent.,  while  the  organic  matter,  not  bitumen,  varies  from  i  to 
6  per  cent. 

An  average  analysis  of  the  crude  material  from  the  lake  is  as 
follows : 

Bitumen    66  per  cent. 

Water    31  per  cent. 

Mineral   matter    I  per  cent. 

Organic  matter,  not  bitumen 2  per  cent. 

In  this  case,  as  with  Trinidad  asphalt,  the  only  element  to  be 
eliminated  is  water,  and  this  is  done  in  the  same  manner. 

The  asphalt,  although  considerably  softer  than  Trinidad,  is 
dug  in  a  similar  manner  and  loaded  into  small  side-dump  cars  run- 
ning on  a  portable  track.  These  cars  are  pushed  by  hand  to  the 
terminal  station  on  the  shore  of  the  lake,  where  they  are  dumped 
into  boxes  contained  on  flat  cars.  These  cars  are  then  taken  by  the 
locomotive  to  the  wharf  on  the  Guanoco  River,  about  five  miles 
distant,  and  dumped  directly  into  the  vessel,  if  one  is  alongside, 
otherwise  they  are  dumped  on  the  shore  of  the  river,  where  there  is 
considerable  storage  place. 

As  the  material  is  softer  than  Trinidad  asphalt  it  is  necessary 
to  have  the  hold  of  the  steamer  or  sailing  vessel  divided  into  com- 
partments in  order  that  the  material  may  not  move  too  freely.  If 
this  were  not  done,  the  sailing  vessel  would  get  such  a  list  in  sail- 
ing for  any  length  on  one  tack  that  it  would  be  impossible  to 
get  her  on  the  other  tack,  and  the  vessel  would  finally  capsize. 
This  same  difficulty  to  a  less  extent  would  also  occur  in  steamers 
where  no  provision  for  bulkheads  was  made.  There  is  now  at  the 
Bermudez  lake  a  refining  plant. 

The  first  pavement  laid  with  this  material  was  on  Woodward 
Avenue,  Detroit,  in  1892.  Since  then,  it  has  come  into  general  use 


36  ASPHALTS.  [CHAP.  v. 

in  different  cities  of  the  country.  When  refined,  the  asphalt  con- 
tains of  bitumen  97.22  per  cent.;  mineral  matter,  1.50,  and  organic 
matter,  1.28.  The  bitumen  is  composed  of  petrolene  77.90  and 
<asphaltene  22.10  per  cent.  The  specific  gravity  is  1.08.  The  Ber- 
mudez  asphalt  has  also  found  great  favor  from  civil  engineers,  and 
large  quantities  have  been  used  in  reservoirs  and  other  large  con- 
struction work;  the  largest  contract  calling  for  its  use  is  in  the 
Rapid  Transit  Tunnel  in  New  York,  where  all  walls  in  contact  with 
the  earth  were  waterproofed  with  felt  and  the  Venezuela  bitumen. 
From  Perdenales  some  shipments  have  been  made  and  at  Mara- 
caibo  a  large  refinery  has  just  been  erected. 

It  has  been  thought  by  some  scientists  that  all  the  Trinidad 
and  Venezuela  asphalts  have  a  common  origin  in  volcanic  erup- 
tions in  the  Gulf  of  Paria. 

Since  the  publication  of  the  article  on  Trinidad  asphalt  there 
has  been  received  a  copy  of  a  most  interesting  report  on  the  Pitch 
Lake  and  its  surroundings  submitted  to  the  Governor  of  Trinidad 
by  acting  Surveyor-General,  Edmonstone  Hodgkinson,  under  date 
of  January  14,  1824.  After  three-quarters  of  a  century  the  state- 
ments of  his  impressions  have  been  verified,  and  his  views  are  an 
interesting  addendum  to  the  literature  on  the  subject. 

He  stated  that  the  Lake  is  situated  upon  the  top  of  a  ridge, 
about  25  or  30  feet  above  the  level  of  the  sea,  from  which  there 
is  a  fall  at  three  sides,  on  the  North  and  West  towards  the  sea,  and 
on  the  East  towards  the  interior  of  the  country.  It  is  principally 
towards  the  North  that  the  Lake  empties  itself  into  the  sea  (if  the 
expression  may  be  used  of  that  which  has  no  sensible  motion),  but 
the  formation  of  the  stream,  of  pitch  from  the  lake  to  the  sea,  a 
distance  of  about  a  mile  and  a  half,  is  too  apparent  from  the  fact, 
to  be  mistaken. 

The  pitch  which  the  lake  presents  to  the  view  is  by  no  means 
the  whole  the  district  furnishes,  the  lake  is  merely  the  part  over 
which  the  soil  has  not  spread,  so  as  to  permit  the  growth  of  grass 
and  wood  on  it,  but  there  is  a  vast  quantity  of  pitch  from  it,  de- 
tached in  portions,  particularly  to  the  northward  up  to  and  upon 
the  seashore,  and  to  the  westward  upon  the  estate  of  the  late 
Madame  Boussac,  now  held  by  Messrs.  Montrichard,  Labastide 
and  Saubot. 

The  different  qualities  of  pitch  observed  are  three  in  number, 
of  which  two  may  be  said  to  be  inexhaustible,  the  deficiency  of  any 


"ASPHALTS' 


VENEZUELA    ASPHALT.  37 

that  is  taken  away  being  quickly  supplied  by  reproduction.  These 
are  the  pitch  of  the  lake  and  the  liquid  pitch  found  on  the  lot  of 
M.  Saubot,  on  both  of  which  the  volcanoes  and  the  matter  rising 
to  the  surface  from  them  are  distinctly  visible.  The  liquid  pitch 
found  is  in  detached  spots,  sometimes  near  to  and  sometimes  at 
some  hundreds  of  yards  distant  from  each  other  upon  the  land  of 
M.  Saubot,  and  the  land  called  Ozon's,  now  also  belonging  to  M. 
Saubot.  These  spots  which  are  said  to  be  about  twenty,  and  of 
which  ten  or  twelve  were  visited,  are  circular,  of  about  30  feet  in 
diameter,  with  the  volcano  in  the  center  from  which  a  bubble  like 
that  of  boiling  water  rises  and  bursts  about  every  minute.  The 
pitch  is  so  nearly  liquid  that  the  specimen  brought  up  was  raised 
with  a  stick  and  let  to  run  from  it  into  a  narrow-mouthed  jar  at 
8  o'clock  in  the  morning  with  the  thermometer  at  79  degrees. 

The  nearer  to  the  volcano  that  the  pitch  is  taken  the  more 
liquid  it  is,  being  then  about  the  consistence  of  tar  when  prepared 
for  use  on  board  ship,  but  this  liquidity  ceases  on  its  removal, 
although  it  is  restored  by  exposure  to  the  sun  in  this  climate.  The 
third  sort  of  pitch  differs  in  the  external  appearance  from  both  the 
foregoing;  it  is  neither  liquid  like  that  last  spoken  of,  nor  in  a 
mass  like  that  of  the  lake,  but  it  is  found  under  the  surface  and  in 
the  immediate  vicinity  of  the  liquid  volcanoes  in  dumps  or  blocks 
about  the  usual  size  of  pieces  of  sea-coal  taken  out  with  the  soil, 
so  loose  that  they  may  be  taken  out  with  a  cutlass  or  any  instru- 
ment sufficiently  strong  to  remove  the  earth.  This  pitch,  when  the 
earth  is  washed  off,  appears  blacker  than  that  of  the  end  of  the  lake. 
It  may  be  that  it  was  visible,  for  the  spots  which  contain  earth  are 
not  found  in  contact.  On  the  contrary  the  liquid  pitch  abounds 
upon  the  land  of  Saubot,  nearer  the  lake,  and  the  latter  is  mostly 
found  further  off  and  upon  the  land  called  Ozon's. 

If  the  pitch  in  blocks  exists  to  any  considerable  depth — which 
there  is  no  reason  to  disbelieve,  but  which  fact  is  known — there 
will  be  found  sufficient  for  almost  any  purpose,  but  it  cannot  be 
called  inexhaustible  with  the  confidence  applicable  to  the  other 
kinds,  because  its  reproduction  is  not  visible. 

Common  experiments  for  fathoming  the  volcanoes  have  been 
tried  in  vain — large  sticks  60  feet  long  have  been  swallowed  per- 
pendicularly in  the  course  of  a  few  hours.  A  line  would  not  an- 
swer the  purpose,  because  it  could  not  be  redrawn.  Mules  a"nd 
oxen  have  been  frequently  lost  on  them. 


38  ASPHALTS.  [CHAP.  v. 

Reverting  to  the  lake  and  to  the  assertion  that  it  empties  itself 
into  the  sea,  it  may  be  observed  that  the  whole  natural  savannah  of 
La  Brea,  abou  a  mile  and  a  half  in  length  and  about  a  quarter  of  a 
mile  in  width,  is  entirely  pitch  over  which,  except  that  part  which 
is  kept  clear  for  the  road,  the  soil  has  contrived  to  spread  a  thin 
covering  of  itself  upon  which  the  fox-tail  and  other  coarse  grasses 
grow.  And  this  savannah  is  evidently  the  stream  by  which  the 
pitch  of  the  lake  is  emptied  into  the  sea,  however  long  the  time 
may  be  that  its  passage  occupies ;  but  that  there  is  a  motion  is  cer- 
tain, both  by  the  houses  in  the  village  of  La  Brea  on  the  seashore, 
which  are  sometimes  raised  "a  foot  or  two  more  at  one  end  than 
the  other,  continue  so  for  a  year  then  the  road  which  is  annually 
made  from  the  lake  to  the  village  by  cutting  out  the  watercourses 
with  hatchets,  is  again  filled  with  pitch  before  the  return  of  the 
period. 

A  fourth  sample  of  pitch  has  been  brought  up,  being  that 
found  at  the  village  on  the  seashore.  The  intention  of  this  is  that 
it  may  be  ascertained  whether  the  pitch  has  deteriorated  in  quality 
in  its  passage  from  the  lake  to  the  sea,  as  if  it  has  not,  it  may  be 
cut  out  on  the  seashore  at  the  very  prow  of  the  boat  that  would 
take  it  and  the  carriage  from  the  lake  would  be  saved. 

There  is  a  bar  off  Point  La  Brea,  but  the  anchorage  for  ship- 
ping is  good  inside.  Off  the  shore  the  pitch  under  the  sand  has 
made  the  water  shallower  than  it  would  otherwise  be. 


CHAPTER  VI. 
CUBAN  ASPHALT. 

THE  Cuban  asphalt  industry  has  not  yet  been  fully  developed, 
but  recently  has  been  brought  prominently  to  notice  in 
consequence  of  a  report  prepared  for  the  U.  S.  Government  by 
Mr.  T.  Wayland  Vaughan  at  request  of  General  Leonard  Wood. 
It  will  be  readily  understood  that  during  the  Cuban  revolution 
nothing  was  done  in  the  way  of  working  deposits,  but  prior  to 
that  period,  some  fifteen  years  ago,  attempts  had  been  made  to 
utilize  the  Cuban  asphalt  for  street  pavements ;  there  was  a  project 
to  mix  the  asphalt  with  clay  and  other  ingredients,  but  no  success- 
ful results  were  obtained,  and  work  attempted  at  Washington 
proved  a  failure. 

At  the  World's  Fair  in  Chicago  some  may  remember  the  solid 
block  of  asphaltum  weighing  1,024  pounds,  which  was  exhibited  by 
Mr.  Otto  D.  Droop,  and  which  was  analyzed  by  M.  Leon  Malo  as 

Pure   bitumen    70.00  per  cent. 

Foreign    matter    24-5o  per  cent. 

Water 5.50  per  cent. 


100.00  per  cent. 

This  came  from  the  asphalt  mine  known  as  "Angela  Elmira," 
which  is  located  about  five  miles  from  the  town  Bejucal  in  the 
Province  of  Habana,  and  which  was  then  owned  by  the  West 
Indies  Co. 

The  present  owners  made  their  first  shipment  to  the  United 
States  in  January,  1901,  and  brought  their  material  before  the  Dis- 
trict of  Columbia  authorities  in  a  practical  way  by  demonstrating 
that  a  good  paving  mixture  could  be  obtained  by  the  blending  of 
the  material  with  a  pure  California  liquid  asphalt. 

Professor  Dow  in  his  last  official  report  said  of  the  sample  of 
crude  asphalt  from  the  "Angela  Elmira"  mine  and  a  sample  of 
California  maltha :  "A  proper  combination  of  this  asphalt  and  flux 
produce  a  cement  that  from  all  indications  will  rank  among  the 
best  for  paving,"  and  portions  of  two  streets  in  Washington  were 


40  ASPHALTS.  [CHAP.  vi. 

last  year  laid  with  this  mixture.  This  material,  which  is  a  hard 
asphalt,  is  of  course  applicable  to  many  purposes  other  than  that 
of  paving. 

Mr.  Vaughan  in  his  report  says  that  the  occurrence  of  mineral 
pitch  or  asphalt  in  the  Island  of  Cuba  has  been  known  since  the 
time  of  the  Conquest.  In  the  "General  History  of  the  Antilles," 
by  Oviedo,  published  in  1535,  mention  is  made  of  a  spring  of  pitch 
near  the  coast  in  the  Province  of  Puerto  Principe. 

This  material  was  used  with  an  admixture  of  grease  for  paint- 
ing the  hulls  of  vessels.  The  same  author  mentions  the  occurrence 
of  pitch  upon  the  shores  of  yabana  Bay,  where  it  was  also  used  for 
a  similar  purpose.  The  presence  of  this  mineral  was  noted  by 
Humboldt,  who  visited  the  islands  in  1803,  and  it  was  mentioned 
both  in  the  personal  narrative  of  his  voyage  and  in  his  essay  upon 
the  Island  of  Cuba.  It  is  probable  that  Humboldt  visited  some  of 
the  localities  which  have  since  become  prominent  as  asphalt  mines 
in  the  vicinity  of  Habana.  He  reports  that  it  occurs  in  the  serpen- 
tine rocks  in  the  form  of  fissure  veins.  He  observed  also  some 
fluid  bituminous  material  of  the  nature  of  petroleum  running  out 
of  fissures  in  the  same  rock. 

In  1828  La  Sagra,  published  in  "Anales  de  Ciencias,  Agricul- 
tra,  Comercio  y  Artes,"  a  journal  formerly  printed  in  Habana,  a 
somewhat  extended  account  of  the  occurrence  of  asphalt  in  the 
vicinity  of  Habana.  Reference  has  also  been  found  to  a  memoir 
on  the  bituminous  deposits  by  one  Navarro,  published  in  1829,  and 
another  by  Moisant,  in  1857,  entitled  "Memoria  sobre  los  Produc- 
tos  Bitumenosos  de  la  Isla  de  Cuba."  There  is  no  question  that 
asphalt  is  to  be  found  in  every  Province  in  Cuba,  but  its  commer- 
cial worth,  as  stated  by  Mr.  Vaughan,  should  be  carefully  consid- 
ered before  large  investments  for  developing  are  made  by  capi- 
talists. 

Cuban  maltha  has  been  imported  in  some  quantities  for  fluxing 
purposes.  Of  this  quality  of  bitumen,  Mr.  J.  L.  Hance,  in  a  con- 
sular report,  says  near  what  was  formerly  the  town  of  Sabanillo  de 
la  Palma,  about  30  miles  east  of  Cardenas  and  some  four  miles 
west  of  Hato  Nuevo,  on  the  north  side  of  the  railroad,  is  the  well 
of  J.  B.  Hamel.  This  well  is  sunk  to  a  depth  of  about  80  feet  in 
serpentine  rock,  and  into  it  oozes  a  thick  mineral  tar. 

The  material  is  drawn  out  by  hand  power,  bucket  and  windlass 
being  used.  The  output  is  about  20  barrels  per  day.  In  the  vicin- 


£  £ 

td  >• 


II 


M   O 


'A  S  P  H  A  L  T  S' 


CUBAN    ASPHALTS.  41 

ity  of  this  well  are  two  others,  one  about  300  feet  further  east  and 
the  other  about  600  feet  to  the  west.  The  mode  of  occurrence  of 
the  mineral  is  the  same.  No  area  of  limestone  was  discovered 
associated  with  the  asphalt,  but  fragments  were  struck  in  the  well. 

About  a  mile  southwest  of  Mina  Hamel  and  about  300  feet 
north  of  the  railroad  is  another  area  of  natural  tar  wells  or  springs ; 
one  well  is  said  to  be  60  feet  deep.  Maltha  has  exuded  from  it 
over  a  considerable  portion  of  the  immediately  surrounding  sur- 
face. The  area  of  mineral  tar  occurs  within  a  shallow  topographic 
basin.  There  are  hills  occurring  on  both  the  north  and  south  sides 
rising  to  75  or  100  feet  above  the  included  depression. 

The  elevation  at  Mina  Hamel  is  probably  not  more  than  25  or 
30  feet.  One  hole  in  this  vicinity,  according  to  H.  E.  Peckham, 
was  fired  during  the  last  insurrection  and  burned  for  four  months 
until  a  heavy  rain  finally  put  it  out.  At  present  the  ground  for 
70  or  80  feet  around  this  hole  is  covered  with  coke.  The  well  itself 
is  full  of  rain  water  upon  which  float  masses  of  vegetation 
stuck  together  with  bitumen  that  comes  from  below.  A  pole 
pushed  down  into  the  water  8  or  9  feet  meets  resistance  in  a  soft, 
yielding  material,  and  if  this  can  be  brought  to  the  surface  it  will 
be  seen  to  be  the  same  as  that  in  the  neighborhood. 

In  Mr.  Hance's  account  of  the  submarine  deposits  of  asphalt 
from  the  Bay  of  Cardenas  he  says :  "The  deposits  in  the  bay  from 
which  asphalt  has  been  taken  are  four  in  number  and  of  two 
grades.  No.  I  is  in  the  western  part  of  the  bay  and  produces  a 
very  fine  grade  of  practically  pure  asphalt,  used  in  the  United 
States  for  the  manufacture  of  varnish. 

I  have  myself  seen  a  serviceable  varnish  made  by  the  simple 
process  of  dissolving  this  quality  of  asphalt  in  turpentine.  Asphalt 
has  been  taken  from  this  deposit  in  large  quantities  for  the  last  21 
years.  Recently,  however,  the  work  has  not  made  rapid  progress, 
owing  to  the  frequent  caving  in  of  the  sides  of  the  shaft. 

The  mode  of  operation  is  almost  primitive.  A  lighter  is 
moored  over  the  shaft,  which  is  from  80  to  125  feet  in  depth — 
varying  according  to  the  rapidity  with  which  the  asphalt  is  re- 
moved and  replenished.  A  long  iron  bar  with  a  pointed  end  is 
raised  by  a  winch  on  board  the  lighter  and  allowed  to  fall,  so  that 
its  own  weight  detaches  portions  of  the  asphalt,  which  is  about  as 
friable  as  cannel  coal,  and  has  much  of  its  appearance.  The  gloss, 
however,  is  more  brilliant.  After  a  sufficient  quantity  has  been  de- 


42  ASPHALTS.  [CHAP.  vi. 

tached,  a  common  scoop-net  is  sent  down  and  filled  by  a  diver — not 
in  a  diving  suit." 

Mr.  William  Palmer,  of  the  United  States  National  Museum, 
says  that  of  the  asphalts  in  the  Province  of  Pinar  del  Rio,  the  mines 
entitled  Rodas  Concepcion  and  Magdalena,  belonging  to  Don  Ra- 
mon Balsinde,  as  well  as  the  sugar  plantations,  Canas  and  Toma- 
sita,  on  which  these  are  located,  are  at  the  head  of  the  extensive 
Bay  of  Mariel.  These  are  mines  worked  under  the  open  sky, 
upon  masses  of  asphalt,  notable  for  their  dimensions,  especially 
the  mine  Magdalena  in  plantation  Tomasita,  which  measures  in 
the  part  already  laid  bare  by.  the  works,  12  meters  of  thickness 
and  more  than  100  in  length.  This  mass  lies  in  the  direction  of 
west-southwest  to  east-northeast,  and  is  probably  a  continuation 
of  the  other  two  mines  situated  on  the  neighboring  plantation 
of  Canas. 

Mr.  Wm.  Palmer  says  that  on  the  rough  exposed  surface  of 
the  reef  at  Mariel  there  are  patches  of  asphaltum  from  I  inch  co 
6  or  8  inches  in  diameter  and  rarely  more  than  y2  inch  thick.  They 
occur  always  in  the  higher  portion  of  the  rock  between  cavities, 
'and  appear  to  have  been  drawn  out  by  the  heat  of  the  sun. 

One  mile  south  of  Mariel  Bay  is  a  deposit  of  asphaltum  which 
has  been  quarried  to  a  depth  of  about  50  feet.  Several  wagon 
loads  were  taken  to  the  barracks  at  Guanajay.  It  is  barely  possible 
that  this  locality  corresponds  to  one  of  the  two  mines  above  de- 
scribed. Mr.  Palmer  states  that  there  are  other  occurrences  of 
asphalt  eight  or  ten  miles  to  the  southwest. 

Near  the  town  of\Banes,  between  Mariel  and  Habana,  are  two 
other  mines,  known  as  San  Jose  and  Constancia,  which  are  the 
property  of  Mr.  Henry  L.  Cranford.  These  mines  have  never  been 
worked  extensively,  and,  according  to  Salterain,  the  production 
scarcely  reached  400  tons  during  the  two  years  preceding  1883. 

In  the  Province  of  Matanzas,  nine  or  ten  miles  northwest  of 
Matanzas  ,about  one  mile  east  of  north  of  the  property  known  as 
El  Recro,  now  owned  by  Captain  L.  H.  Mattair,  U.  S.  A.,  there 
is  an  occurrence  of  asphalt  on  the  north  side  of  a  hill.  The  asphalt 
oozes  out  in  liquid  form  and  impregnates  the  surface  sands  and 
gravel,  cemeting  them  into  a  kind  of  a  pudding-stone.  It  also 
accumulates  in  small  quantities  in  ditches  which  have  been  dug 
here  for  the  purpose  of  testing  the  yield. 

There  is  no  great  amount  of  the  asphalt  escaping  to  the  sur- 


CUBAN    ASPHALTS.  43 

face,  although  the  yield  might  be  materially  increased  by  sinking 
a  shaft  on  the  fissure.  It  exudes  apparently  from  small  fissures  in 
the  serpentine  near  its  contact  with  a  hard  limestone,  the  serpen- 
tine forming  the  hill  above  and  the  limestone  lying  on  its  lower 
flank.  The  latter  rock  has  no  perceptible  odor  of  asphalt  or 
petroleum,  and  therefore  probably  has  no  association  with  the 
origin  of  the  bituminous  material. 

Another  reported  occurrence  of  asphalt  is  in  the  vicinity   :>f 
Guamacaro,  between  the  towns  of  Limonar  and  Cardenas. 


CHAPTER  VII. 
AMERICAN    BITUMINOUS    LIMESTONE. 

AMERICAN  natural  bituminous  limestone  has  been  before 
referred  to  as  found  in  Uvalde  County,  Texas.  In  a  recent 
report  formulated  for  the  United  States  Bureau  of  Geological  Sur- 
vey of  the  Department  of  the  Interior,  Mr.  George  H.  Eldridge 
states  that  the  only  deposit  worked  in  this  somewhat  extensive 
field  is  that  by  the  Uvalde  Asphalt  Company,  eighteen  miles  west 
of  Uvalde,  and  eight  miles  southeast  of  Cline,  a  station  on  the 
Southern  Pacific  Railroad,  with  which  it  is  connected  by  rail. 

The  limestone  quarried  primarily  consists  of  what  seems  to 
be  an  assemblage  of  minute  organisms,  together  with  a  conspicu- 
ous proportion  of  crystalline  calcite.  Molluscan  remains,  often  of 
large  size,  are  also  present.  Through  the  mass  of  the  rock  there 
is  a  high  per  cent,  of  interstitial  space,  which  in  some  instances 
may  even  exceed  the  solid  portions.  In  addition  to  the  interstitial 
space,  properly  so-called,  are  cavities  produced  by  the  removal 
of  the  molluscan  remains  and  other  of  vug  like  character. 

These  spaces,  institial  and  other,  are  occupied  by  bitumen,  but 
it  is  evident  by  the  many  examples  throughout  the  bed  that  the 
supply  was  inadequate  to  completely  fill  the  intervals  provided, 
or  that  the  channels  to  the  same  were  blocked  before  the  filling 
was  accomplished.  An  interesting  feature  in  connection  with  the 
larger  cavities  of  the  rock  is  the  presence  of  white,  well-crystallized 
calcite,  which  has  replaced  the  shells  of  the  molluscan  forms  orig- 
inally present,  and  has  also  been  deposited  in  secondary  form  on 
the  walls  of  the  cavities,  whether  of  animal  origin  or  vugs.  The 
bitumen,  in  passing  into  these  cavities,  has  filled,  in  instances,  every 
angle  made  by  the  crystalline  lining  of  the  walls,  and  fractures  of 
the  rock  now  yield  most  beautiful  cross-sections. 

The  asphalt  itself  has  a  brilliant  luster  when  fractured,  but 
when,  in  the  broken  rock,  that  portion  which  formerly  was  in 
contact  with  the  walls  of  the  cavities  it  filled  is  exposed,  the  bril- 


'A  S  P  H  A  L  T  S' 


AMERICAN    BITUMINOUS    LIMESTONE.  45 

liant  luster  is  wanting,  a  surface  of  dead  black  replacing  it.  The 
material  is  brittle,  and  in  hardening  apparently  suffered  no  shrink- 
age. The  asphaltic  limestone  itself  is  tough  and  unyielding. 

Throughout  the  rock  occasional  particles  of  pyrite  are  ob- 
served, and  there  are  instances  in  which  both  these  and  calcite 
have  been  caught  up  and  carried  on  in  the  flow  of  the  infiltrating 
asphalt.  The  molluscan  cavities-  are  varied  in  form  and  size,  and 
embrace  those  of  both  bivales  and  univalves.  Among  the  former 
is  one  resembling  a  Gryphaea;  among  the  latter,  a  long,  tubular 
form  showing  delicate  striations  on  its  surface.  This  especially 
abounds. 

A  feature  of  the  bed  is  the  presence  of  small  gray  to  white 
bodies  of  calcite  of  such  close  texture  that  they  remained  unim- 
pregnated  by  the  bitumen.  Such  bodies  are  excessively  hard,  are 
lacking  in  interstitial  spaces,  and  even  have  the  tubes  which  they, 
too,  carry  rilled  with  secondary,  earthy  and  crystalline  calcite.  In 
the  northern  part  of  the  quarry,  rock  of  this  composition  and 
texture  may  equal  the  more  porous,  bitumen-bearing  portion,  im- 
parting to  the  bed  a  marbleized  and  mottled  effect. 

In  this  portion  of  the  quarry  there  is  also  a  transverse  or 
vertical  joint  plane,  which  is  of  interest  chiefly  because  of  the 
impoverishment  that  has  taken  place  in  the  bed  on  either  side 
— on  the  north  to  a  distance  of  8  inches  to  I  foot,  on  the  south 
less.  The  line  between  the  impoverished  and  rich  portions,  as 
exhibited  by  their  brown  and  black  colors,  respectively,  is,  too, 
quite  as  distinct  as  the  joint  plane  and  practically  parallel  with  it 
throughout. 

The  amount  of  bitumen  in  the  rock  of  this  quarry  is  said  to 
vary  between  IQ  and  20  per  cent.,  14  and  15  being  common,  while 
20  occurred  in  one  locality  in  a  body  of  considerable  proportions. 
The  structure  of  the  rock  has  naturally  had  a  most  material  in- 
fluence upon  the  distribution  of  the  bitumen. 

The  extent  of  the  enriched  body  of  limestone  at  the  Uvalde 
Company's  quarry  had  not  been  determined  either  laterally  or  in 
depth,  but  it  could  be  easily  and  economically  ascertained  with  a 
drill,  for  the  position  of  the  bed  is  at  most  but  a  short  distance  from 
the  surface.  The  outcrop  of  the  limestone  shows  it,  however,  to 
have  been  more  or  less  impregnated,  and  doubtless  with  important 
interruptions,  throughout  an  area  of  several  miles. 

The  area  of  rock  removed  at  this  quarry,  though  somewhat 


46  ASPHALTS.  [CHAP.  vn. 

irregular,  is  between  300  and  400  feet  in  diameter,  while  the  depth 
quarried  averages  perhaps  15  feet,  the  enriched  rock  below  this 
passing  beneath  water  level.  The  section  of  limestone  exposed  is: 
At  the  top,  3  or  4  feet  of  barren,  drab,  or  buff  rock  of  the  composi- 
tion described  as  general  for  the  unimpregnated  portions  of  the 
bed,  this  everywhere  forming  the  cap;  beneath  this,  a  zone  i  or  2 
feet  thick  of  impoverished  brown  rock,  breaking  more  easily  than 
the  richer  portions  below;  finally,  the  bitumen  bearing  bed  of  high 
per  cent.,  18  feet  in  full  depth  to  the  floor  of  the  pit. 

The  material  from  this  mine  has  been  used  for  about  200,000 
square  yards  of  street  pavement  in  the  cities  of  San  Antonio,  Hous- 
ton, Shreveport,  Waco  and  Palestine,  Texas.  The  heavy  freight 
has  prohibited  its  use  in  Eastern  cities. 

The  specifications  for  this  asphalt  as  drawn  up  by  Mr.  E.  G. 
Truehart,  City  Engineer  of  San  Antonio,  calls  for  the  natural  rock 
asphalt  to  contain  from  12  to  14  per  cent,  of  natural  bitumen,  80 
to  88  per  cent,  of  pure  bicarbonate  of  lime,  and  must  be  free  from 
quartz,  sulphates,  iron  pyrites  or  aluminum. 

The  rock  is  first  crushed  and  reduced  to  a  powder,  after  which 
it  must  be  heated  in  a  revolving  cylinder  from  250  degrees  to  320 
degrees  Fahrenheit,  depending  on  the  time  of  year  and  distance  to 
be  hauled.  Nothing  whatever  shall  be  added  to  or  taken  from  the 
powder  obtained  by  grinding  the  bituminous  rocks.  No  binder  will 
be  required  if  this  material  is  used,  but  care  must  be  taken  to  leave 
the  top  surface  of  the  concrete  of  sufficient  roughness  to  obtain  a 
good  bond. 

The  powder  must  be  carefully  leveled  and  spread  in  one  con- 
tinuous sheet  in  such  a  manner  that  it  will  be  2  inches  in  thickness 
after  compression.  It  must  be  hot  when  spread,  and  therefore,  if 
so  ordered  by  the  engineer,  it  shall  be  brought  to  the  street  in 
boxes  that  can  be  handled  by  two  men  and  dumped  at  the  exact 
place  where  it  is  to  be  spread.  The  tamping  must  begin  imme- 
diately after  the  spreading  of  the  powder,  at  first  carefully,  and  then 
gradually  augmenting  the  force  with  tools  made  especially  for  the 
purpose,  heated  to  the  proper  temperature  in  portable  furnaces. 

The  entire  surface  must  be  thoroughly  tamped  with  hand 
tampers  and  then  gone  over  with  smoothing  irons,  till  it  presents  a 
glossy  appearance.  Dry  hydraulic  cement  will  then  be  swept  over 
the  top,  and  the  surface  rolled  with  a  steam  roller  weighing  no  less 
than  six  tons.  The  rolling  will  be  first  done  longitudinally  and  then 


AMERICAN    BITUMINOUS    LIMESTONE.  47 

transversely  at  an  angle  of  45  degrees  from  both  sides  of  the  street, 
and  continued  until  the  pavement  has  been  thoroughly  compressed. 

Great  care  must  be  exercised  in  making  a  proper  bond  with 
the  surface,  which  has  been  already  laid  and  allowed  to  cool.  First 
all  loose  and  all  uncompressed  powder  must  be  removed  from  the 
edges  of  the  pavement  and  the  joints  swept  perfectly  clean. 

A  gasoline  heater  must  then  be  used  in  heating  thoroughly  the 
rough  edges  of  the  pavement  already  laid,  before  new  material  is 
added;  the  spreading,  tamping  and  rolling  then  goes  on  as  before, 
the  end  intended  being  to  leave  no  trace  of  the  junction.  If  so 
ordered  instead  of  applying  the  material  to  the  rough  edge,  the 
said  edge  shall  be  cut  with  an  axe  so  as  to  leave  a  clean  smooth 
joint ;  this  joint  must  then  be  well  painted  with  a  coating  of  asphaltic 
cement  before  the  heated  powder  is  laid  against  it. 

Bituminous  limestones  are  also  found  in  Indian  Territory,  but 
of  very  imperfect  impregnation.  Of  that  in  the  Buckhorn  district 
Mr.  Eldridge  reports  that  the  rock  of  the  quarry  is  very  massive, 
with  a  texture  varying  between  earthy,  granular  and  crystalline. 
The  crystalline  texture  is  the  most  prevalent  in  the  upper  half  of 
the  deposit,  the  earthy  and  granular  in  the  lower  half.  The  aver- 
age per  cent,  of  bitumen  in  the  quarried  rock  is  between  5  and  6, 
based  on  samples  from  the  stock  piles. 

Different  portions  of  the  bed,  however,  vary  somewhat  in  rich- 
ness, that  quarried,  which  is  the  granular  crystalline,  being  regarded 
as  the  most  satisfactory.  The  color  is  a  deep  chocolate  brown  in  the 
more  homogeneous,  granular,  and  finely  crystalline  portions,  vary- 
ing to  brownish  gray  in  those  more  coarsely  crystalline;  the  first 
described  is  the  richer  in  bitumen. 

The  rock  is  stratified,  but  the  bedding  is  extremely  heavy  in  the 
lower  middle  portion.  Near  the  top  and  bottom  the  beds  are  from 
2  to  10  feet  thick,  and  the  divisional  planes  are  especially  pro- 
nounced. Bodies  of  highly  crystalline  calcite  are  irregularly  but 
profusely  distributed  through  the  upper  third  of  the  mass,  and  in 
their  poverty  in  bitumen  are  in  marked  contrast  to  the  general 
rock  of  the  quarry. 

About  70  feet  from  the  top  of  the  limestone  is  a  narrow  belt  in 
which  blue  translucent  chert  abounds,  and  there  is  a  trace  of  chert 
also  at  the  base  of  the  bed. 

In  the  lower  portion  of  the  mass  as  quarried  is  a  zone,  about 
20  feet  in  width,  that  presents  the  aspect  of  having  originally  been 


48  ASPHALTS.  [CHAP.  vn. 

laid  down  as  a  calcareous  mud.  It  is  of  a  browner  color  than  the 
crystalline  granular  rock,  and  is  regarded  of  slightly  lower  value. 

In  this  connection  it  may  be  noted  that  there  are  many  instances 
of  muddy  texture  in  the  limestones  throughout  the  Buckhorn  dis- 
trict, which,  coupled  with  other  features,  are  suggestive  of  a  sedi- 
mentary origin  for  the  greater  number  if  not  for  all  of  them. 

The  effect  of  the  calcite  bodies  in  the  upper  portion  of  the  lime- 
stone upon  impregnation  is  noteworthy,  the  universally  close  union 
of  their  crystals  preventing  infiltration  into  their  substance  of  more 
than  the  merest  trace  of  bitumen,  and  often  none  whatever.  In  the 
portion  of  the  limestone  surrounding  these  bodies,  however,  infiltra- 
tion has  been  free,  or  at  least  in  proportion  to  the  absence  of  the 
calcite  structure. 

In  the  Brunswick  district  there  is  a  quarry  of  very  similar  for- 
mation, the  earthy,  granular,  and  crystalline  texture  are  all  re- 
peated; the  barren  calcite  bodies  are  present,  in  equal  contrast  with 
the  general  mass  of  the  rock;  the  calcareous  is  as  readily  identified 
in  one  locality  as  in  the  other,  and  each  variety  of  rock  in  texture 
shows  the  same  difference  in  the  degree  of  impregnation. 

If  there  be  a  difference  in  the  rocks  of  the  two  localities  it  is 
in  an  apparently  more  general  distribution  of  the  calcite  bodies 
through  the  rock  of  the  Brunswick  quarry  and  a  possible  slight 
lowering  in  consequence,  of  an  otherwise  equally  maintained  aver- 
age in  the  bitumen  percentage. 

A  feature,  too,  conspicuous  in  certain  portions  of  the  Bruns- 
wick pit,  is  the  filling  of  fracture  cracks  with  pure  bitumen,  derived, 
probably,  by  infiltration  from  the  main  body  of  the  rock.  This  rock 
has  been  used  for  the  manufacture  of  asphalt  Mastic  which  has  been 
laid  extensively  in  Western  cities  for  brewery  floors. 


1  1 


'A  3  P  H  A  L  T  S' 


CHAPTER  VIII. 
BITUMINOUS  ASPHALT  SANDSTONE  ROCK. 

NATURAL  bituminous  asphalt  sandstone  rock  as  in  contradis- 
tinction to  limestone,  appears  to  be  peculiarly  of  American 
origin.  It  is  found  in  Kentucky,  Missouri,  Indian  Territory,  Texas, 
Utah  and  California. 

The  difference  between  the  limestone  and  sandstone  bituminous 
impregnation  appears  to  be  most  marked,  it  is  seen  that  the  bitumen 
softens  the  limestone  and  is  homogeneous,  whereas  the  bitumen 
with  the  sand  remain  two  distinct  substances  although  they  can  be 
compressed  into  a  compact  mass  when  heated. 

The  most  important  fields  operated  are  those  in  Kentucky  and 
a  quantity  of  pavement  has  been  laid  with  the  sandstone  in  Louis- 
ville. Professor  Eldridge  says  that  bitumens  in  Kentucky  occur  as 
impregnations  of  sandstones.  They  are,  perhaps  the  result  of  ex- 
posure in  outcrop  of  oil-bearing  strata,  the  petroleum  having  thus 
been  converted  by  loss  of  the  lighter  hydro-carbons  and  by  oxida- 
tion into  a  product  of  asphaltic  nature. 

The  sandstones  thus  impregnated  carry  in  freshly  picked  faces 
of  the  quarries  from  4^  to  7^  per  cent,  of  bitumen,  amounts  that 
would,  perhaps  show  material  increase  at  a  distance  from  the  ex- 
posed surfaces.  The  horizons  at  which  the  bitumens  occur  include 
the  conglomerate  at  the  base  of  the  coal  measures,  a  sandstone  a 
little  above,  and  the  several  sandstones  of  the  Chester  series  of  the 
lower  carboniferous.  The  enriched  beds  are  met  in  outcrop  in  many 
localities  in  Breckenridge,  Grayson,  Edmonson,  Warren  and  Logan 
counties. 

In  Breckenridge  county,  The  Breckenridge  Asphalt  Co.  has 
opened  two  quarries  about  100  yards  apart,  near  the  point  of  the 
ridge  between  the  forks  of  Lost  Run,  two  miles  south  of  Garfield. 


50  ASPHALTS.'  [CHAP.  vm. 

Each  is  about  200  feet  in  diameter  and  shows  practically  the  same 
section  of  sandstone,  and  variation  in  thickness  or  in  the  degree  of 
impregnation  being  such  as  may  be  expected  betwen  different  points 
in  the  same  bed. 

The  sandstone  is  of  sharp,  fine-grained  quartz.  Of  the  14  feet 
enriched,  the  lower  7  or  8  are  said  to  carry  an  average  of  8  per 
cent,  (varying  between  6  and  10)  of  bitumen  and  constitute  the 
shipping  rock.  The  sample  collected  by  Professor  Eldridge  con- 
tained a  little  less  than  6  per  cent.  Above  this  the  amount  of  bitu- 
men is  considerably  diminished  and  with  exceptions  the  rock  is 
treated  as  refuse.  There  is  no  distinct  line  of  demarcation  be- 
tween the  richer  and  poorer  horizons,  a  wavy  zone  of  gradation  2 
or  3  feet  in  width  existing  between  the  two.  This  zone  affords  a 
certain  amount  of  second  grade  rock,  to  which  is  occasionally 
added  material  of  equally  low  per  cent,  that  may  chance  to  occur 
in  the  underlying  portion  of  the  bed.  This  second  grade  rock  is 
then  occasionally  made  available  by  thoroughly  mixing  it  with 
the  highest  grade  from  the  mine. 

A  feature  of  interest — not  only  in  the  Breckenridge  quarries 
but  in  all  visited — is  the  impoverishment  that  takes  palce  for  6  or 
8  inches  on  either  side  of  joint  planes.  Beyond  this  the  rock 
maintains  its  average  bitumen  contents. 

In  Grayson  county  exploitation  has  been  made  by  Schillinger 
Bros,  and  Dr.  Wilham  F.  Breyfogle.  One  of  the  Schillingers' 
mines  at  Black  Rock  produces  a  rock  which  is  a  medium-grained 
massive  sandstone,  of  a  thickness  of  8  or  10  feet,  the  lower  5  of 
which  is  impregnated  with  bitumen  to  an  average  of  perhaps  6 
per  cent,  distributed  in  greater  proportion  through  the  lower  3 
feet  of  the  mass.  Of  the  Breyfogle  quarry  near  Tar  Hill  Pro- 
fessor Eldridge  reports  that  the  rock  is  a  sandstone  composed  of 
medium  to  coarse  grains  of  quarty,  much  coarser,  as  a  rule,  than 
the  material  of  the  Leitchfield  flag.  The  latter  rock  is  also  gen- 
erally thin  bedded,  hard,  and  durable,  and  makes  an  excellent 
flagging,  all  in  marked  contrast  to  the  features  of  the  Big  Clifty 
sandstone. 

The  impregnated  zone  at  the  Breyfogle  quarry,  embraces  a 
thickness  of  about  10  feet  in  the  upper  portion  of  the  Big  Clifty 
sandstone.  Of  this  the  lower  5  or  6  feet  are  of  sepecial  richness 
carrying  a  somewhat  variable  amount  of  bitumen,  indeed,  but,  per- 
haps, an  average  of  7  per  cent.  Upon  passing  under  greater  cover 


BITUMINOUS    ASPHALT    SANDSTONE    ROCK.  51 

it  is  quite  possible  that  the  upper  portion  of  the  zone  will  show  an 
increase  in  its  contents. 

Between  the  two  portions  there  is  no  definite  line  of  division. 
An  incidental  feature  at  this  quarry  is  the  heavy  cross  bedding, 
irrespective  of  which,  however,  the  bitumen  appears  to  have  im- 
pregnated the  rock  to  a  general  level,  thus  making  productive  at 
one  point  a  layer  that  is  apparently  unproductive  at  another.  An- 
other feature  is  the  degree  in  which  the  bitumen  seeps  from  the 
exposed  faces  of  the  quarry,  even  from  levels  in  the  sandstone 
where  there  are  no  visible  division  planes. 

Where  crevices,  either  natural  or  formed  by  blasting,  have 
remained  open,  such  seepage  becomes  of  added  interest  as  a  pos- 
sible suggestion  regarding  the  formation  of  gilsonite  and  other 
veins  of  related  material.  The  bitumen,  always  of  a  highly  gummy 
consistency  after  leaving  its  bed,  is  seen  slowly  trickling  from  the 
sides  of  the  crevice,  deposting  one  layer  over  another,  yet  the 
several  layers  blend  in  a  homogeneous  mass  but  a  short  time  after 
the  flows.  Held  in  the  bitumen,  also,  are  small  rock  fragments 
that  have  tumbled  into  the  crevice  and  have  been  taken  up  by  the 
slowly  flowing  mass.  Such  material  is  now  hard,  even  semi-brittle 
in  instances. 

In  Edmonson  county  the  geological  horizon  of  the  bituminous 
sandstone  of  the  Bee  Spring  region  was  traced  by  Mr.  S.  D.  Averitt 
from  Leitchfield,  15  miles  north.  The  same  succession  of  beds  is 
encountered  in  this  section  as  in  the  region  of  the  Schillinger  No. 
2  Prospect,  but  in  more  extended  order.  The  roofing  limestone  of 
the  Chester  appears  at  Harold  Hill,  5  miles  south  of  Leitchfield. 
It  is  here  about  6l/2  feet  thick  and  rests  upon  6  to  8  inches  of  marl. 
It  has  the  same  lithological  and  paleontologic  characters  as  in 
other  places  in  western  Kentucky. 

There  are  many  deposits  of  bituminous  sandstone  in  this  part 
of  Edmonson  county,  and  in  many  places  small  tar  springs,  rather 
than  saturated  sandstone,  are  found.  One  deposit  of  consider- 
able extent  is  found  2  miles  northeast  of  Bee  Spring,  on  the  farm 
of  Mr.  J.  Meredith,  and  another  i^  miles  south  of  Bee  Spring. 
None  of  the  deposits  are  worked  and  their  value  is  undetermined. 

The  deposits  already  described  are  found  along  the  eastern 
border  of  the  coal  measures;  those  that  follow  occur  along  the 
•southern  edge  of  this  area.  The  deposits  of  bituminous  sandstone 
in  Warren  county  are  confined  to  its  extreme  northern  end,  the 


52  ASPHALTS.  [CHAP.  vm. 

lower  coal  measure — Chester  terrane  entering  it  only  to  a  limited 
extent.  But  two  quarries  are  opened  within  the  county,  neither, 
however,  more  than  a  prospect. 

They  are  located  on  what  is  known  as  the  Cherry  Farm,  at 
Youngs  Ferry,  on  Green  River,  12  miles  north  of  Bowling  Green. 

Two  openings,  about  300  yards  apart,  have  been  made  in  the 
bituminous  deposits  of  this  locality.  One,  the  eastern,  near  the 
summit  of  the  ridge,  is  being  developed  by  the  Green  River  As- 
phalt Co. ;  the  other,  the  western,  is  controlled  by  the  Sicilian  As- 
phalt Company,  but  has  remained  idle  since  the  shipments  of  a  few 
tons  of  trial  rock. 

This  latter  deposit,  an  impregnated  zone  in  the  basal  conglo- 
merate of  the  carboniferous,  is  about  10  feet  thick  and  occurs 
about  15  feet  beneath  the  top  of  the  stratum.  The  enriched  rock 
continues  for  an  undetermined  distance  to  the  west,  but  on  passing 
eastward  the  bed  seems  to  become  barren ;  this,  too,  within  a  few 
hundred  feet. 

The  matrix  of  the  impregnated  zone  is  essentially  quartz  sand> 
a  few  pebbles  being  distributed  through  it  in  small  assemblages 
here  and  there.  As  in  other  instances,  the  lower  half  of  the  zone 
is  the  richer,  carrying  at  the  old  quarry  breast  about  7  per  cent. 
of  bitumen.  The  bitumen  continually  seeps  both  from  the  face  oft 
the  small  openings  and  from  the  out-crop,  forming  small  pools  a 
few  inches  across  at  the  base  of  the  ledge. 

The  deposit  of  the  Green  River  Asphalt  Company  is  in  the 
bitumen  bearing  sandstone  overlying  the  main  basal  conglo- 
merate, from  which  it  is  separated  by  20  to  30  feet  of  yellow  and 
gray  shale. 

The  bed,  as  exposed  at  the  time  of  examination,  showed  a 
thickness  uncovered  of  about  6  feet,  all  impregnated,  but  in  vary- 
ing degree,  the  lower  2^  feet  of  excellent  promise.  The  sample 
taken  by  Mr.  Eldridge  within  5  or  6  feet  of  the  outcrop,  yet  in 
normal  looking  rock,  yielded  about  7  per  cent,  of  bitumen.  At 
one  point  the  upper  portion  of  the  bed,  also,  showed  considerable 
enrichment,  indicating  that  upon  passing  beneath  cover  the  entire 
6  feet  might  become  available  for  shipping.  The  matrix  of  the 
rock  is  a  clear,  sharp,  quartz  sand. 

The  deposits  of  bituminous  sandstone  in  Logan  county  lie  in 
its  northern  half,  in  the  Chester  division  of  the  lower  carbonifer- 
ous. A  single  quarry,  that  of  the  Standard  Asphalt  Company,  has 


ASPHALT   PAVING   PLANT   OP  THE   ASPHALT   CONSTRUCTION 
COMPANY,   OP  NEW  YORK. 


BITUMINOUS    ASPHALT    SANDSTONE    ROCK,  53 

been  opened,  about  5  miles  northeast  of  Russellville,  in  the  Big 
Clifty  sandstone.  There  is  also  a  prospect  about  2  miles  north- 
west of  this  at  the  same  horizon.  Mr.  Averitt  also  reports  one  or 
two  other  deposits,  unopened,  at  this  horizon,  near  Homer,  still 
farther  north. 

The  region  about  Higginsville,  Lafayette  county,  is  the  only 
portion  of  Missouri  in  which  bituminous  rock  has  thus  far  been 
found,  with  a  possible  exception  near  Odessa,  15  miles  west,  where 
also,  evidences  are  said  to  exist.  The  only  attempt  at  development 
has  been  by  the  Higginsville  Quarry  Company,  on  land  near  the 
Soldiers'  Home,  i^  miles  northwest  of  the  town,  where  a  pit  20 
feet  in  diameter  has  been  made  for  trial  purposes. 

California  has  several  deposits  of  bituminous  sandstone  and 
of  malthas  in  sand.  The  City  Street  Improvement  Co.  has  exten- 
sive quarries  near  Santa  Cruz.  The  bituminous  sandstones  which 
constitute  the  product  of  these  quarries  are  essentially  an  aggre- 
gate of  minute  to  medium-sized  quarz  grains.  In  addition  to 
these,  there  is  a  slight  admixture  of  a  feldspar  like  material  sug- 
gestive of  the  derivation  of  the  sediment  from  the  adjacent  gran- 
ite area.  There  is  also  present  at  times  a  slight  amount  of  iron 
and  a  clayey  looking  material  in  fine  grains. 

Only  the  quartz,  however,  is  conspicuous.  This  is  subangular 
to  rounded.  It  is  in  the  interstices  of  this  rock  that  the  bitumen  is 
held  to  an  extent  of  between  14  and  16  per  cent,  in  the  average 
specimen.  The  rock  varies  somewhat  in  hardness,  but  on  the 
whole  is  soft,  crumbling  under  the  sun's  heat,  very  tenacious,  and 
gummy  to  the  touch.  Its  color  is  normally  black  to  brownish- 
black,  weathering  to  a  gray  on  exposure  to  the  atmosphere.  As 
to  the  coarseness  of  the  material  constituting  the  bed,  while  the 
mass  of  it  is  of  a  medium  grain,  there  are  bodies  of  small  extent 
of  coarser  stuff,  imparting  a  gritty  and  at  times  even  a  fine  con- 
glomerate appearance,  the  pebbles  also  being  of  quartz,  though 
occasionally  one  of  clay  is  found.  The  temperature  of  the  atmos- 
phere, according  as  it  is  cold  or  hot,  renders  the  rock  either  brittle 
or  soft. 

There  is  but  little  variation  from  the  above  features  in  the 
quarries  that  are  opened  on  the  main  bed  at  the  lower  horizon. 
Moreover,  the  members  of  this  bed  themselves  varied  but  little 
from  each  other.  The  company  has  laid  several  streets  with  this 
material  in  Santa  Cruz  and  some  in  San  Francisco.  I  understand, 


54  ASPHALTS.  [CHAP.  viii. 

however,  that  they  have  lately  laid  the  ordinary  street  mixtures 
prepared  in  eastern  cities,  using  the  California  pure  bitumen  with 
sand  added.  This  is  from  the  fact  that  freight  rates  are  too  ex- 
pensive to  allow  of  any  distant  freightage  on  the  natural  material. 
The  same  trouble  exists  in  the  use  of  the  Kentucky  bitumin- 
ous limestones  and  it  can  only  be  used  to  advantage  in  the  neigh- 
borhood of  the  mines  or  in  places  where  exceptionally  low  rates  of 
transportation  are  obtainable. 


CHAPTER  IX. 
MANJAK  AND  UINTAITE. 

BARBADOS  produces  a  bitumen  which  is  known  as  manjak, 
the  origin  of  this  nomenclature  is  indeterminable,  it  is  a 
purely  local  term  and  may  have  been  given  by  the  negroes  or  pos- 
sibly have  been  handed  down  from  the  Indians  who  inhabited  the 
island  prior  to  1605,  when  the  crew  of  the  "Olive  Blossom"  took 
possession  of  the  Island  in  the  name  of  "James  King  of  England 
and  of  this  island." 

The  geology  of  the  Island  does  not  seem  to  afford  the  positive 
source  of  the  bitumen.  From  one  point  of  view  the  land  rises  in 
a  succession  of  limestone  and  coral  terraces  which  indicate  dif- 
ferent periods  of  upheaval  from  the  sea.  From  another  there  is 
nothing  to  be  seen  but  a  mass  of  abruptly  rising  rocks. 

The  gullies  or  ravines,  the  result  no  doubt  of  volcanic  agency, 
are  very  numerous  radiating  from  the  high  semi-circular  ridge  of 
the  Coralline  formation  in  a  very  regular  manner  to  the  west, 
north  and  south  but  not  to  the  East,  where  the  coral  rocks  end 
abruptly. 

The  chalky  soil  of  the  district  called  Scotland  (from  its  as- 
sumed resemblance  to  the  scenery  of  the  Highlands  )contains  "in- 
fusoria" and  is  altogether  different  from  the  deposits  of  the  coral 
anmials  which  form  the  superficial  area  of  six-sevenths  of  the 
island  (91,000  acres).  Besides  the  chalk  or  marl,  sandstone  is 
found  in  this  dtstrict. 

The  Scotland  formation  also  contains  a  blue  clay  sometimes 
interstratified  with  the  sandstone.  It  is  in  this  section  of  the 
Island  that  the  bitumen  was  found  and  to  Mr.  Walter  Merivale, 
C.  E.,  must  be  given  the  credit  of  exploiting  the  sources  and  de- 
veloping the  industry  of  mining  the  product. 

In  a  paper  read  before  the  Federated  Institution  of  Mining 
Engineers,  Mr.  Merivale  stated  that  having  found  the  manjak  in 
pockets  apparently  in  no  great  number  and  of  no  great  size,  he 
considered  that  it  suggested  the  fact  that  the  mineral  found  in  the 


56  ASPHALTS.  [CHAP.  ix. 

pockets  must  have  broken  off  a  main  body  and  later  having  found 
a  vien  where  the  ground  was  not  disturbed  by  slips,  his  conclusion 
was  that  there  is  beneath  the  island  an  enormous  reservoir  of 
liquid  bitumen  which  is  still  trying  to  force  its  way  to  the  surface. 

In  the  Conset  district,  there  is  a  hill,  or  rather  a  piece  of  the 
vliff,  about  300  feet  long,  on  the  coast,  called  Burnt  Hill,  which  is 
described  by  Messrs.  Jukes-Browne  and  Harrison,  in  their  pam- 
phlet on  the  geology  of  Barbados,  as  being  impregnated  with  bitu- 
men. Impregnated  it  certainly  has  been,  but  the  impregnation 
took  place  very  many  feet  below  the  level  it  at  present  occupies, 
and  before  it  was  thrust  up  through  the  calcareous  sandstones  and 
marls.  These  still  stand  on  either  side  of  it  in  alternate  strata, 
from  3  to  12  inches  thick,  exposed  on  the  face  of  the  cliff,  and 
rapidly  and  more  rapidly  inclined  upwards  as  they  near  the  in- 
truded mass  of  shale.  The  shale,  moreover,  shows  no  stratifica- 
tion, but  is  simply  a  huge  mass.  Mr.  Merivale  sunk  shafts  on  both 
sides  of  it  and  found  it  below  the  marl.  This  shale  or  bituminous 
clay,  has  the  following  analysis : 

Moisture 7.52 

Ash 76.19 

Carbon   14.32 

Hydrogen  (not  included  in  moisture) 1.05 

Oxygen,  etc 0.92 

As  the  shaft  increased  in  depth  thin  veins  of  hard  manjak  were 
found,  and  others  of  liquid  manjak,  and  of  semi-liquid  manjak.  In 
the  Conset  district,  the  coral  capping  has  been  removed,  and  the 
manjok  exposed  in  more  than  one  spot. 

When  met  with,  some  way  below  the  surface,  the  blue  clay  is 
soft  and  treacherous,  the  fissues,  which  divide  it  up  into  a  million 
blocks,  contain  bitumen  or  water,  and  the  blocks  slide  from  their 
places  as  soon  as  the  miner's  pick  removes  the  supporting  rock  or 
manjak  from  before  them.  Higher  up,  the  blue  clay  seems  to  be 
almost  a  different  formation,  and  is  as  hard  as  rock,  not  unlike 
chalk,  and  crossed  and  recrossed  by  thin  streaks  of  manjak  and 
of  gypsum. 

Large  quantities  of  iron  pyrites  are  also  ,found  here  and  there 
in  it,  in  nodules  and  in  very  thin  veins. 

The  manjak  veins  are  thrust  up  through  all  the  formations 
except  the  coral,  which  prot>ably  indicates  that  the  intrusion  oc- 


Q 

li 


is 

<6     02 


•A  S  P  H  A  L  T  S' 


MANJAK    AND    UINTAITE.  57 

curred  before  the  coral  was  formed,  or  it  may  mean  that  it  occurred 
after  it  was  formed,  but  was  unable  to  get  through  it.  In  the 
latter  case,  however,  the  ends  of  the  veins  would  be  flattened  out 
against  the  bottom  of  the  coral,  instead  of  ending  in  thin  streaks 
in  the  softer  lower  formation. 

The  rain  having  washed  away  this  lower  formation  after  the 
removal  of  the  coral  cap,  the  thin  outcrop  is  exposed,  and  at  times 
a  stream  cutting  its  way  down  a  hillside,  carves  out  a  piece  of  the 
vein  that  crosses  its  path,  leaving  exposed  a  section  of  the  vein  on 
each  side  of  the  gully ;  or  the  waves  eat  away  the  cliffs,  and  exhibit 
the  cross  section  of  a  vein  running  out  to  sea. 

It  was  upon  one  of  these  stream  exposed  veins  that  Mr.  Meri- 
vale  began  work  a  few  years  ago,  and  it  is  from  this  vein  or  pocket, 
as  the  geologists  are  understood  still  to  call  it,  that  he  has  ex- 
tracted a  large  tonnage. 

The  following  are  analyses  of  Merivale  manjak  and  of  Trini- 
dad glance-pitch : 

Trinidad 

Merivale      Glance- 
manjak.        pitch. 

Specific  gravity 1.123  I-I39 

Melting  point 420°  F.        360°  F. 

Matter  soluble  in  carbon  bisulphide 97%  88% 

Ash  2.32  7.44 

Ash,  color Reddish.     Grayish. 

Loss  on  heating 2.61  9.4* 

Iodine  absorption 42.2%          42.0% 

Organic  dust 0.69  4.56 


*Per  cent,  after  heating  to  500°  F.  for  two  hours. 

Others  have  followed  Mr.  Merivale's  example  and  have  mined 
the  manjak  which  is  in  good  demand  for  insulating  material,  var- 
nishes, waterproof,  etc.,  and  it  has  to  a  great  extent,  superseded 
for  use  in  high  class  varnishes  Egyptian  and  Cyrian  asphalts,  which 
it  closely  resembles  in  composition  and  appearance.  This  asphalt 
has  not  had  the  advantage  of  the  extensive  advertising  given  to 
other  bitumens  and  the  writer  does  not  call  to  mind  the  exhibit  of 
this  mineral  at  any  of  the  great  expositions. 

Possibly  the  advantages  of  this  method  of  bringing  products 


58  ASPHALTS.  [CHAP.  ix. 

before  the  public  is  not  as  popular  as  hitherto,  for  it  was  noticeable 
that  at  the  Pan-American  Exposition  only  one  exhibit,  that  of  the 
Barber  Asphalt  Co.,  was  on  view,  while  at  the  Chicago  "World's 
Fair"  a  great  number  of  companies  were  represented. 

Uintaite  (gilsonite  )is  a  similar  material  to  the  Barbados  man- 
jak;  it  is  found  in  the  vicinity  of  the  boundary  line  (between  Col- 
orado and  Utah).  Professor  Eldridge  has  described  it  as  a  black, 
tarry-looking  substance  of  most  brilliant  luster,  normally  of  ab- 
solutely homogeneous  texture,  and  exceedingly  brittle.  Its  frac- 
ture is  coarsely  conchoidal.  In  mining,  it  gives  off  a  fine  chocolate 
brown  dust,  most  penetrating,  to  skin  and  lungs.  Sufficiently  near 
the  outcrop  of  the  vein  to  be  influenced  by  atmospheric  agencies, 
it  loses  its  brilliant  luster  for  a  dead  black  surface,  but  a  fresh 
fracture,  no  matter  in  how  small  a  particle,  shows  its  brilliancy 
still  present,  indicating  a  change  to  an  inconsiderable  depth  only. 

Under  atmospheric  influences,  also,  uintaite  shows  a  fine  col- 
umnar structure  at  right  angles  to  the  walls  of  the  vein  and  to  a 
distance  of  about  6  inches  from  them.  This  structure  has  been 
recognized  by  Wurtz,  Lesley  and  others  in  grahamite,  and  by  Les- 
ley is  called  "Pencillate."  In  addition  to  the  columnar,  there  may 
be  developed  a  cuboidal  structure,  in  some  instances  by  a  further 
transverse  separation  of  the  pencillate  rays  in  others  independent 
of  these.  In  the  upper  10  or  15  feet  of  a  vein  the  latter  structure 
not  infrequently  prevails  through  a  large  proportion  of  the  uin- 
taite, shading  laterally  into  the  two  pencillate  zones  at  the  sides. 
It  would  seem  quite  probable  that  this  structure,  pencillate  and 
cuboidal,  is  inherent  in  the  material  having  originated  perhaps  im- 
mediately after  its  injection  into  the  fissure  from  cooling  or  from 
pressure. 

The  walls  of  the  uintaite  veins  are  usually  impregnated  with 
the  mineral  to  depths  of  from  6  inches  to  2  feet,  though  the  shales, 
on  account  of  their  close  texture,  do  not  permit  this  to  such  a  de- 
gree as  the  sandstones.  The  line  between  the  impregnated  and 
non-impregnated  portions  of  the  wall  rock  is  usually  somewhat  in- 
definite, but  instances  are  not  wanting  of  the  sharpest  demaraca- 
iton. 

The  region  in  which  the  unitate  (gilsonite)  veins  are  found 
extends  between  the  parallels  of  39  degrees  30  minutes  and  40  de- 
grees and  30  minutes,  and  the  meridians  of  109  degrees  and  no  de- 
grees 10  minutes,  or  from  a  point  4  or  5  miles  within  the  Colorado 


MANJAK    AND    UINTAITE.  59 

line,  westward  for  60  miles  into  Utah.  Larger  veins  are  somewhat 
scattered,  one  lying  about  3^2  miles  due  east  of  Fort  Duquesne,  a 
second  in  the  region  of  Upper  Evacuation  Creek,  and  the  two  or 
three  others  of  chief  importance  in  the  vicinity  of  White  River  and 
the  Colorado  Utah  line.  Besides  these,  there  is  a  14-inch  vein  near 
the  western  edge  of  the  area  in  the  vicinity  of  the  fortith  parallel ; 
another  of  equal  size  about  6  miles  southeast  of  the  junction  of  the 
Green  and  White  rivers ;  a  third  in  a  gulch  4  or  5  miles  northwest 
of  Ouray  Agency,  west  of  the  Duyuesne  River,  and  a  number  from 
one-sixteenth  of  an  inch  to  I  foot  in  thickness  in  an  area  about  10 
miles  wide,  extending  from  Willow  Creek  eastward  for  25  miles 
along  both  sides  of  the  Green  and  White  rivers. 


CHAPTER  X. 
LATE  EUROPEAN  WORK. 

WHILE  preparing  this  matter  the  author  made  a  trip  to  Eu- 
rope and  took  the  opportunity  to  study  there  the  develop- 
ments in  the  asphalt  industry.  He  visited  Mr.  W.  H.  Delano  in 
Paris,  whom  he  found  busy  in  the  preparation  for  putting  up  works 
on  the  Mahmoudieh  Canal  in  Alexandria,  Egypt,  where  his  com- 
pany have  a  considerable  amount  of  work  to  do  in  compressed 
asphalt. 

A  model  of  bituminous  concrete  fortification  attracted  the 
writter's  attention  and  he  was  informed  that  a  casement  12  meters 
by  6  metres  by  4^  metres  had  been  constructed  of  the  same  ma- 
terial for  the  French  arm  officials  in  1886  at  the  Bourges  Camp 
(Department  Cher),  at  which  bombshells  charged  with  melinite  had 
been  fired  and  that  the  construction  stood  the  test  for  fifteen  min- 
utes, while  one  of  the  same  built  of  hydraulic  cement  concrete  was 
shattered  at  the  first  discharge. 

In  London  the  writer  met  Mr.  H.  D.  Blake,  director  and  gen- 
eral manager  of  the  Limmer  Asphalt  Paving  Company.  He  stated 
that  Limmer  mastic  and  asphalt  and  Montrotier  Seyssel  mastic  as- 
phalt are  mineral  rock  asphalts  prepared  only  by  the  company. 
The  ungritted  mastic  asphalt  is  composed  of  not  less  than  15  per 
cent,  of  bitumen  and  85  per  cent,  of  fine  rock  asphalt  powder.  The 
gritted  mastic  asphalt  is  composed  of  15  to  18  per  cent,  of  bitumen 
and  from  82  to  85  per  cent,  of  fine  rock  asphalt  powder,  with  an 
addition  of  from  10  to  20  per  cent,  of  fine  specially  prepared  grit, 
according  to  requirements. 

The  various  purposes  to  which  this  company's  mastic  asphalt 
may  be  put  are  almost  innumerable,  and  to  merely  mention  a 
few,  Mr.  Blake  states  that  these  mastic  asphalts  are  being  very 
largely  adopted  by  architects,  and  engineers  for  roofs,  floors, 
bridges,  barracks,  fortifications,  powder  magazines,  quays, 
wharves,  barns,  footways,  pavements,  graneries,  drill-grounds, 
breweries,  stables,  coach-houses,  courtyards,  railway  platforms, 
warehouses,  basement  floors,  covering  of  railway  and  other  arches, 


TRIMBLE  PLACE,  NEW  YORK,  X.  Y. 

Paved  with   Xeuchatel   Rock   Asphalt   Paves,    finished  with   Non- 
Slippery  Wearing  Surface,  cast  iron  gutter  and  wheel  plates. 


'A  S  P  H  A  L  T  S* 


LATE    EUROPEAN    WORK.  6l 

damp  course  to  horizontal  walls,  vertical  work  to  face  of  walls, 
swimming  baths,  skating  rinks,  tennis  courts,  lining  reservoirs, 
slaughter  houses,  market  places,  piggeries,  dog  kennels,  garden 
paths,  and  playgrounds  to  public  schools  of  the  Metropolis  and 
leading  provincial  towns  in  the  United  Kingdom  of  Great  Britain. 

Mineral  rock  mastic  asphalt  does  not  absorb  impurities  and 
can  easily  be  cleansed,  and  its  introduction  into  Indian  and  other 
eastern  cities  would  do  much  to  facilitate  the  work  of  sanitation 
now  so  much  needed  in  the  East,  especially  for  the  lining  of  the 
usual  open  side  drains  and  filth  carriers  of  the  bazaars. 

The  substitution  for  the  rough  and  imperfect  brick  gutters,  of 
a  smooth  jointless  surface  of  mineral  rock  mastice  asphalt  would 
prove  invaluable,  and  would  do  much  to  remedy  their  present 
offensiveness  and  danger. 

Again,  mineral  rock  mastic  asphalt  used  for  floors  for  public 
and  private  latrines  is,  for  similar  reasons,  much  superior  to  any 
other  kind  of  flooring,  especially  on  account  of  its  durability,  the 
ease  and  rapidity  with  which  it  can  be  cleaned  or  repaired,  and  not 
least,  its  great  sanitary  properties,  because  being  jointless  no  vege- 
table or  animal  refuse  can  lodge  in  crevices  and  decay.  Mineral 
rock  mastic  asphalt  might,  with  advantage,  be  introduced  into  In- 
dian and  other  eastern  hospitals,  barracks  and  public  buildings  as 
floors,  flat  roofing  with  skirting  and  angle  fillets,  damp-proof 
courses,  vertical  work  with  hot  asphalt  applied  to  walls,  also  for 
damp  vertical  walls  where  asphalt  mastic  plates  are  fixed  and  after- 
wards jointed  with  hot  liquid  asphalt. 

Thus  walls  and  foundations  are  made  secure  against  dampness 
of  any  kind,  because  after  its  manipulation  the  mastic  asphalt  be- 
comes impervious  to  air  and  water,  resists  fire,  does  not  burn, 
repels  vermin,  checks  vibration  and  is  a  non-conductor,  and  should 
do  much  to  arrest  the  ravages  of  rats  and  white  ants  and  their 
destructive  effects  of  rot  in  foundations. 

Many  other  situations  in  which  mineral  rock  mastic  asphalt 
may  be  advantageously  used  will  readily  suggest  themselves.  It 
may  be  mentioned,  however,  that  the  Limmer  Asphalt  Paivng 
Co.'s  mastic  asphalts  have  been  laid  in  India,  Ceylon,  China,  South 
Africa,  etc.,  establishing  the  fact  that  mineral  rock  aspahlt  is,  in  the 
end,  a  real  economy,  and  when  properly  laid  withstands  the  ex- 
tremes of  heat,  cold  and  damp,  successfully. 

Mr.  Blake  considers  that  all  horizontal  foundation  walls  to 


62  ASPHALTS.  [CHAP.  x. 

buildings  should  be  covered  with  a  thickness  of  y*  inch  of  mastic 
asphalt  below  the  ground  level  to  prevent  dampness  from  arising. 
Vertical  walls  below  ground  level  should  be  covered  externally  by 
applying  a  thickness  of  ^  mcn  vertically,  viz.,  by  pointing  the 
joints  of  brickwork  with  hot  mastic  asphalt,  then  applying  two 
separate  coats  against  the  wall,  making  in  all  an  average  of  ^4  mch 
in  thickness.  Particular  care  should  be  taken  to  connect  this 
vertical  asphalt  with  that  laid  horizontally  by  adding  an  angle 
fillet.  Amongst  many  other  places  that  might  be  named  where 
this  class  of  work  has  recently  been  most  successfully  executed, 
are  the  horizontal  and  vertical  walls  of  the  new  Admiralty  Build- 
ings, Whitehall. 

Where  walls  under  ground  level  are  of  a  very  damp  nature, 
and  it  is  impossible  to  put  up  the  liquid  mastic  asphalt  in  the  ordi- 
nary manner,  the  Limmer  Asphalt  Paving  Company  for  some 
years  past  have  introduced  their  special  system  of  mastic  asphalt 
plates  which  can  be  easily,  economically,  and  successfully  used, 
viz.,  after  the  mastic  asphalt  plates  are  made  to  the  proper  size,  and 
the  backs  of  which  are  specially  roughed  to  form  a  key,  the  joints 
of  the  wall  are  raked  out  and  a  thin  bed  of  cement  mortar  laid  on 
the  back  or  rough  part  of  the  plate  and  pressed  against  the  wall, 
fixed  in  courses  with  broken  joints.  When  the  cement  has  set, 
make  good  the  joints  with  hot  mastic  asphalt;  the  whole  then  be- 
comes one  solid  sheet  and  is  not  only  damp  proof  but  adds  con- 
siderable strength  to  the  walls. 

The  same  care  must  be  taken  in  making  good  the  connection 
of  the  vertical  plate  work  with  the  horizontal  damp  course  by  add- 
ing an  angle  fillet.  These  plates  are  recommended  for  all  walls, 
either  internal  or  external,  but  in  all  new  buildings  it  is  a  great 
advantage  to  execute  the  work  externally. 

This  method  is  particularly  suitable  for  lining  internal  and  ex- 
ternal damp  walls,  reservoirs,  sewage  tanks,  strong  rooms,  etc. 
In  the  year  1890  this  company  supplied  asphalt  for  lining  the  Mala- 
bar Hill  Reservoir,  Bombay,  and  sent  out  a  foreman  to  superintend 
the  work,  which  was  carried  out  to  the  complete  satisfaction  of  the 
authorities. 

It  has  always  been  a  difficult  matter  to  lay  with  any  success 
asphalt  over  suspension  bridges,  especially  on  account  of  the  ex- 
cessive vibration.  This  company,  however,  recently  covered  with 
their  mastic  asphalt  the  carriageway  of  the  well  known  Clifton 


LATE    EUROPEAN    WORK.  63 

Suspension  Bridge,  near  Bristol,  England,  and  successfully  got 
over  the  difficulty  by  covering  the  wood  flooring  with  canvas,  well 
nailed  down,  so  as  to  form  a  surface  to  receive  the  mastic  asphalt, 
then  laid  l/2  inch  of  rich  bituminous  mastic  as  an  elastic  bottom 
coat,  following  with  a  second  layer  of  less  bituminous  mastic  I  inch 
thick,  making  in  all  il/2  inches  in  thcikness.  At  special  intervals, 
an  elastic  bituminous  joint  was  specially  inserted  I  inch  in  depth, 
made  transversely  to  prevent  the  mastic  asphalt  from  cracking. 
This  new  departure  has  proved  exceedingly  satisfactory,  the  car- 
riageway not  suffering  at  all  during  the  severe  and  violent  gales 
of  wind  to  which  this  bridge  has  since  been  exposed. 

In  covering  a  suspension  bridge  with  a  steel  bent  plating  bot- 
tom as  a  foundation,  it  has  been  proved  that  by  filling  in  the  hol- 
lows with  Portland  Cement  Concrete,  so  as  to  form  the  camber  to 
receive  the  mastic  asphalt,  the  cement  concrete  does  not  withstand 
the  vibration  and  eventually  cracks  and  crumbles  into  dust. 

This  company  recently  covered  the  carriageway  and  footways 
of  the  Menai  Suspension  Bridge  over  the  Menai  Straits,  North 
Wales,  and  instead  of  cement  concrete,  laid  down  their  bituminous 
rock  mastic  asphalt  concrete,  by  filling  in  the  hollows  of  the  plat- 
ing to  the  proper  formation  of  the  carriageway,  and  laid  the  mastic 
asphalt  in  two  coats  in  the  usual  manner  with  great  success. 

In  Hamburg  the  writer  met,  at  the  office  of  Messrs.  Prins  & 
Sturken,  agents  of  the  "Industrie-Gesselschaft  fur  Steine  und  Er- 
edn"  of  Madgeburg,  the  then  managing  director  of  that  company, 
Mr.  Bruchmann,  who  informed  him  that  his  company  was  a  new 
addition  to  asphalt  producers  and  that  it  possesses  collective  min- 
ing prerogatives  over  420  acres,  in  Madgeburg,  and  works  the 
crude  asphaltum  beds  there  on  mining  principles. 

Magdeburg  Asphalt  is  the  name  under  which  the  Asphalt 
Products  of  the  Industrial  Society  for  Stone  and  Earth  is  known 
in  America.  The  first  importation  of  their  mastic  was  made  by  the 
Boorman  Anderson  Asphalt  Co.  in  1904,  and  from  1905  to  1908  a 
large  quantity  has  been  shipped  from  Hamburg  and  Bremen  to. 
New  York  and  Philadelphia,  and  it  has  been  used  extensively  in 
Western  Packing  Houses  and  in  such  work  as  the  Hall  of  Chem- 
istry of  Syracuse  University  and  on  the  esplanade  of  the  famous 
Stadium  of  that  institution. 

So  far  as  the  Asphalt  Industry,  in  covering  its  necessities  for 
Mastic,  Stamping  Asphalt,  Asphalt  Slabs  and  Goudrons  will  de- 


ASPHALTS. 


[CHAP.  x. 


pend  on  German  sources,  it  can  only  do  so  by  the  occurrence  of 
the  above  minerals  near  Lobsann  (in  North  Alsatia,  District  of 
Weissenburg  and  about  1^2  hours  distant  from  Worth),  or  through 
the  well-known  works  at  Vorwohle  (in  the  Duchy  of  Brunswick, 
District  Holzminden),  or  those  of  Limmer  (near  Hanover). 

Prof.  E.  Dietrich,  of  the  Royal  Technical  High  School  in  Ber- 
lin, has  therefore  in  his  work  on  "The  Asphalt  Streets,"  in  1882, 
rightly  anticipated  "that  the  Vorwohle  Rock  Asphalt  in  respect  to 
its  employment  as  a  material  for  making  streets  is  possibly  des- 
tined to  play  a  part." 

The  chemical  analyses  of  the  European  Crude  Asphalt  Rock 
gave  the  following  comparative  results.  (See  Table  V.) 

TABLE  V. 


Rock  Asphalt  from 
German  Materials : 

Lobsan 

Limmer    

r  Industrie  Ges 

^  Deutsche  Asph.  Ges 
3  I  Hannov.  Bau  Ges . . 
Haarmann  &  Co ... 

Rehder  &  Co 

Thomae  . 


ANALYSES   OF   CRUDE  ROCK 

Pure 
Bitumen 
per  cent. 
12.32 

14-30 
10.62 
2.40 
5.80 
2.90 
1.40 
0.90 

Industrial  Society  for  Stone  and  Earth, 
hausen  (Krs.  Holzminden). 

Pure 

Rock  Asphalt  from  Bitumen 

Foreign  Materials :  per  cent. 

Val  de  Travers 10.15 

San  Valentino 8.83 

Ragusa 8.92 

Mons 10.20 

Pont  du  Chateau 11.40 

N.  B.— Analysis  results: 

*  according  to  Dietrich. 

**  according  to  Dr.  Fritsch  &  Venator. 

t  according  to  our  own  factory  laboratory. 

J  according  to  Experimental  Station  in  Forli. 


ASPHALT. 

Carbonate 

of  lime 

per  cent. 

71.43 

* 

67.00 

* 

87.14 

** 

91.85 

f 

89.87 

t, 

90.64 

f 

9I-52 

t 

9375 

t 

Limited,  in  Eschers- 

Carbonate 
of  lime 
per  cent. 

88.40  * 

80.00  t 

88.21  * 

84-63  t 

77.52  f 


SIDEWALK   CORNER    OF   SMITHFIETLD    STREET    AND   5TH    AVENUE,  PITTSBURG. 

Laid  with  Kentucky  Rock  Asphalt  Mastic  by  The  Wadsworth  Stone 
&  Paving  Company. 


15 


"ASPHALT  S' 


LATE    EUROPEAN    WORK.  65 

The  Vorwohle  and  Limmer  works  have  united  and  formed  a 
syndicate  in  the  Vorwohle  Asphalt  Verkaufs  Verein  (Society  for 
the  sale  of  Vorv/ohle  Asphalt)  to  which  at  present  belong  the  mines 
and  factories  of  R.  Thomae,  Rehder  &  Co.  (Vorwohle  Asphalt 
Co.),  L.  Haarmann  &  Co.,  the  Deutsche  Asphalt  Actien  Gessll- 
schaft,  the  United  Limmer  and  Vorwohle  Rock  Asphalt  Company 
and  the  Hannoversche  Ban  Gesellschaft. 

The  Asphalt  mining  district  belonging  to  the  Industrial  Com- 
pany comprise  about  420  Brunswick  Morgen  of  2,500  square  me- 
ters =  105  hectares,  that  is,  they  alone  possess  more  Asphalt  land 
than  all  the  other  Vorwohler  Asphalt  works  taken  together.  The 
borings  carried  out  up  to  the  present,  and  other  mining  operations, 
have  proved  that  their  Rock  Asphalt  exists  in  a  thickness  of  eleven 
metres,  of  which  only  about  four  metres  square  are  worked  first  of 
all,  in  the  first  level  by  means  of  galleries  and  drifts  as  well  as 
transverse  headings.  According  to  the  report  of  Dr.  F.  Rinne, 
Professor  of  Geology,  and  Mr.  Hoyer,  Mining  Engineer,  both  of 
the  Royal  Technical  High  School  in  Hanover,  the  rock  which 
has  been  already  reached  suffices  for  at  least  40  years  in  its 
whole  extent,  supposing  the  output  to  be  daily  10  double 
loads. 

Their  Asphalt  Rock  and  crude  powder  are  especially  adapted 
for  mixing  with  the  fatter  foreign  Asphalt  material  from  San  Val- 
entino, Mons,  etc.,  on  account  of  their  considerable  yield  of  bitu- 
men and  high  percentage  of  lime,  as  well  as  the  perfect  freedom 
from  deleterious  secondary  substances. 

For  their  Asphalt  Mastic  they  guarantee  at  least  14  per  cent, 
bitumen,  which,  according  to  experience,  means  a  considerable 
saving  in  Goudron  when  renewed  preparation  for  laying  streets 
is  in  question.  All  authorities  agree  in  the  opinion,  that  the  single 
particles  in  the  asphalt  limestone,  as  well  as  in  its  later  products, 
viz. :  Mastic,  Stamp  asphalt,  etc.,  are  no  longer  held  together  by 
molecular  cohesion,  or  by  a  stony  cement  but  only  by  the  asphalt 
as  a  bituminous  cement.  Thus  this  bitumen  guarantee  is  of  the 
highest  importance  for  every  one  using  Asphalt,  on  account  of  the 
resistance,  elasticity  and  durableness  of  the  Asphalt  materials  em- 
ployed in  street  laying  and  for  other  purposes. 

Brunswick  Asphalt  Mastic. — This  material  has  been  imported 
for  the  last  thirty  years  by  Gabriel  &  Schall,  of  New  York.  It  has 
been  laid  in  many  public  and  private  structures  throughout  the 


66  ASPHALTS.  [CHAP.  x. 

United  States,  and  has  proved  eminently  satisfactory  to  the  owner, 
architect  and  contractor. 

To  insure  the  protection  of  the  trade,  the  genuine  material  is 
put  up  in  cakes  cylindrical  in  shape,  weighing  from  54-55  Ibs.  each, 
and  branded  under  the  registered  trade  mark  (G  &  S). 

By  permission  of  the  importers  we  present  the  analyses 
shown  in  Table  VI.  on  this  and  following  page : 

TABLE  VI. 

ANALYSES  OF  BRUNSWICK  ASPHALT  ROCK,  ASPHALT 
MASTIC  AND  ASPHALT  PAVEMENT. 

Brunswick  Asphalt  Rock. 

Asphaltic  bitumen,  per  cent 9.70 

Carbonate  of  lime,  per  cent 90.30 

100.00 
Brunswick  Asphalt  Mastic. 

Asphaltic  bitumen,  per  cent 15-42 

Carbonate  of  lime,  per  cent 84.58 

100.00 

Brunswick  Apshalt  Pavement. 
As  laid  in  basement  of  276  Canal  Street,  New  York  City: 

Asphaltic  bitumen,  per  cent 1344 

Grit,  per  cent 35-OO 

Carbonate  of  lime,  per  cent 51-56 


100.00 
COMPARATIVE  ANALYSES. 

Neufchatel  Rock,  asphaltic  bitumen  from  12  to  13  per  cent. 
Seyssel  Rock,  asphaltic  bitumen  from  8  to  9  per  cent. 
Brunswick  Rock,  asphaltic  bitumen  9.70  per  cent. 

COMPARATIVE  TESTS  OF  THE  ASPHALT  ROCK  SUB- 
MITTED TO  HEAT. 

Seyssel  Rock  disintegrates  at  250  degrees  Fahr. 
Brunswick  Rock  disintegrates  at  250  degrees  Fahr. 
Neufchatel  Rock  disintegrates  at  200  degrees  Fahr. 


LATE    EUROPEAN    WORK.  67 

TABLE  VI. — Continued. 

COMPARATIVE  TESTS  OF  THE  THREE  ASPHALT  MAS- 
TICS SUBMITTED  TO  HEAT. 

The  results  are  identical  for  all  three. 
Malleable  at  90  degrees  Fahr. 
Soft  at  100  degrees  Fahr. 
Plastic  at  250  degrees  Fahr. 

The  fire  tests  were  also  applied  to  the  different  Mastics  with 
equally  good  results. 

Fire  tests,  Neufchatel  Mastics,  315  degrees  Fahr. 
Fire  tests,  Seyssel  Mastic,  330  degrees  Fahr. 
Fire  tests,  Brunswick  Mastic,  320  degrees  Fahr. 

CONCLUSION. 

The  above  results  are  evidences  of  the  similarity  of  the  three 
named  Asphalt  Mastics,  and  the  Brunswick  Asphaltic  Rock  is 
almost  identical  with  the  Seyssel  Asphaltic  Rock. 

(Signed)  E.  J.  De  SMEDT,  Chemist. 

In  regard  to  this  class  of  Mastic,  so  many  inquiries  have  been 
made  into  the  Modus  Operandi  that  the  following  practical  in- 
structions, prepared  by  David  E.  Sayre,  when  Superintendent  of 
the  New  York  Mastic  Works,  are  appended : 

Kettle  will  lay  about  100  to  105  feet  i-inch  work.  Dimen- 
sions :  Drum,  3  feet  6  inches  high ;  kettle,  I  foot  7  inches  deep 
and  3  feet  4  inches  wide.  Use  about  14  blocks  Mastic  and  about 
50  pounds  Bitumen,  with  about  600  pounds  Grit  for  ordinary  out- 
door walks.  For  indoor  work  about  13  blocks  Mastic,  80  pounds 
Trinidad  and  600  pounds  Grit  for  floors  that  will  be  used  severely 
by  setting  chairs,  etc.,  on  them.  This  would  not  do  for  a  cold 
cellar.  For  this  use  the  same  combination  as  for  outdoor  work, 
or  you  are  liable  to  have  a  crack  in  the  asphalt.  For  this  indoor 
work  you  should  see  that  the  kettles  are  thoroughly  and  almost 
continually  stirred,  and  particularly  from  the  outside  of  the  bot- 
tom of  the  kettle.  The  stirrers  should  be  driven  down,  scraping 
the  side  and  bottom  of  the  kettle.  You  should  have  also  a  scraper 
with  handle  about  54  inches  long,  scraper  about  3  inches  wide, 
scraper  made  from  best  'steel,  and  kept  sharp,  with  which  to 


68  ASPHALTS.  [CHAP.  x. 

scrape  the  sides  and  particularly  the  bottoms  of  your  kettles  each 
evening  until  the  iron  shows  plainly.  When  the  kettles  are  warm 
have  a  board  laid  across  the  top  of  kettle,  the  bottom  chopped 
and  scraped  clean  with  the  long-handled  scraper.  We  would  sug- 
gest for  quadrille  work  to  have  four  additional  squares  added  to 
jour  stamp,  start  your  line  and  set  stamp  first  time  straight,  then 
each  additional  time  set  two  blocks  over  the  last  figure  made  in 
the  work.  This,  with  a  little  care,  will  keep  your  lines  straight  with- 
out using  the  line  more  than  once.  We  think  you  will  find  kettles 
made  in  one  piece  preferable  to  those  with  loose  bottoms ;  also 
have  a  heavy  angle  iron  around  the  top  and  bottom  of  the  drum, 
projecting  inside.  This  supports  the  kettle  on  the  top  and 
strengthens  it  on  the  bottom,  also  leaving  a  smooth  surface  so 
the  drums  will  roll  easily.  Have  your  kettle  fit  in  drum  neatly, 
tout  not  too  tight,  so  they  will  not  spill  out  in  rolling  and  yet  can 
ibe  taken  out  and  put  in  without  too  much  trouble.  The  stirrers 
should  have  a  face  about  7  inches  wide  and  scraping  edge  about 
^  to  2l/>  inches  and  kept  fairly  sharp. 

In  laying  asphalt  always  be  sure  that  the  concrete  is  fully  up 
to  grade  line  and  a  level,  even  surface,  as  cement  and  sand  are 
much  cheaper  than  asphalt,  besides  a  spreader  cannot  do  first- 
class  work  when  attempting  to  spread  uneven  thicknesses  of  as- 
phalt. You  do  not  need  an  absolutely  smooth  surface,  but  an 
even  one  without  depressions  or  bumps  in  it,  and  not  too  dry. 
Try  and  lay  the  asphalt  before  the  concrete  turns  white,  and  just 
after  it  has  set  firmly,  as  it  will  blister  from  the  concrete  being 
either  too  wet  or  too  dry.  You  will  find  the  above  proportions 
for  indoor  work  will  cause  complaints  from  your  labor,  as  it  will 
be  very  stiff  and  will  require  extra  hard  work  to  either  stir  or 
spread,  and  will  require  good  strong  men,  and  should  be  well 
rubbed  with  sand.  The  men  may  kick,  but  your  work  will  be  sat- 
isfactory to  the  party  having  you  do  the  work  and  a  source  of 
satisfaction  to  you  as  well. 

Be  careful  that  the  asphalt  does  not  get  burned  in  the  bottom 
of  the  kettle.  It  is  a  good  idea  to  have  the  last  few  shovels  of  ma- 
terial emptied  into  another  kettle,  and  well  stirred  into  it.  We 
find  one  never  gets  the  kettles  stirred  too  much  after  the  grit  is 
put  in  before  that  it  is  not  so  necessary.  In  laying  good  stiff  work 
use  1/4 -inch  iron  guide  bars,  and  you  will  get  your  full  inch,  and 
on  down  for  thinner  layers;  only  you  will  find  your  material  will 


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'A  S  P  H  A  L  T  S' 


LATE    EUROPEAN    WORK.  69 

have  to  be  softer  as  it  is  laid  thinner,  and  to  make  it  so  requires 
more  Mastic  and  Bitumen  or  Trinidad.  Always  see  that  the  joints 
are  well  heated  before  final  sprading,  keeping  pome  hot  stuff 
ahead  of  the  work  on  the  asphalt  the  spreader  is  joining;  rub 
joints  extra  well. 


CHAPTER  XI. 
TURKISH  AND  OTHER  BITUMENS. 

WHEN  in  London  I  found  that  a  Trukish  bitumen  was  being 
used  for  fluxing  purposes  and  since  had  the  pleasure  of 
meeting  Professor  J.  Edward  Spurr,  of  the  U.  S.  Geological  Sur- 
vey, who  had  just  returned  from  Constantinople.  He  furnished 
me  with  the  following  interesting  information : 

On  the  southwestern  coast  of  Asia  Minor,  north  of  Cape 
Chelidonia,  is  the  famous  ancient  Chimaera  of  the  Greek  stories. 
Here  gases  are  continually  disengaged  from  fissures  and  are 
known  to  have  been  burning  for  2,800  years  atleast,  for  the  phe- 
nomenon was  described  by  Hesiod  before  the  time  of  Homer. 
Tchiatcheff,  the  Russian  geologist,  states  that  the  gas  is  emitted 
from  fissures  in  serpentine  (altered  igneous  rock)  intrusive  into 
limestone. 

It  is  interesting  to  note  in  this  connection  that  burning  foun- 
tains of  gas  were  long  known  in  the  Baku  oil  fields,  beforethe  dis- 
covery of  oil  there.  There  is  also  on  the  coast  of  Albania  (east 
shore  of  the  Adriatic)  the  locality  Polina,  near  Durezzo,  where 
gas  emanates  from  the  summit  of  a  hill  and  often  accidentally 
takes  fire.  The  hill  is  said  to  be  igneous,  but  the  existence  at  the 
foot  of  it  of  an  asphalt  spring  suggests  an  organic  rather  than  a 
volcanic  origin  for  the  gas.  Petroleum  also  has  been  reported 
from  here  and  seems  to  have  been  exported  on  a  small  scale.  This 
hill  was  the  ancient  Apollinia,  and  here  the  priestess  of  the  famed 
Delphic  oracle  sat  and  inhaled  the  fumes  of  gas,  till  dazed,  when 
her  words  were  regarded  as  inspired. 

It  is,  therefore,  an  open  question  as  to  whether  the  escaping 
gas  of  the  Chimsera  (the  modern  Turkish  name  is  Yanartash 
"stone  that  burns"  is  of  organic  origin,  and  indicates  oil  below, 
or  is  volcanic ;  but  the  chances  are  perhaps  in  favor  of  the  former 
alternative,  especially  as  the  igneous  rockc  of  the  locality  (altered 
peridotite)  is  not  one  that  indicates  recent  volcanic  activity. 


TURKISH    AND    OTHER    BITUMENS.  71 

As  is  perhaps  most  often  the  case,  there  seems  to  be  a  general 
connection  between  petroleum  and  natural  asphalt  in  the  Turkish 
Empire.  Asphalt  deposits  are  known  in  a  number  of  lacalities, 
of  which  the  best  known  are  in  Albania,  near  the  Adriatic  and  in 
Palestine. 

In  Albania  asphalt  occurs  at  the  foot  of  the  hill  of  the  Delphic 
oracle,  as  mentioned  above,  also  in  a  large  bed  near  Avlona  and 
other  places.  This  asphalt  was  mined  by  the  anceints  and  is  men- 
tioned by  Posidonius.  The  chief  producing  locality  is  now  Selin- 
itza,  which  is  worked  'by  the  Imperial  Ottoman  Bank.  The  as- 
phalt is  not  of  the  highest  quality,  bringing  about  $13  a  ton  in 
Trieste.  Asphalt  is  reported  from  the  Province  of  Monastir  in 
European  Turkey. 

The  asphalt  in  the  region  of  the  Dead  Sea  (Lake  Asphaltites) 
has  long  been  noted.  There  are  bituminous  springs  at  Nebi  Musa 
which  contain  30  to  40  per  cent,  asphalt. 

What  is  commercially  known  as  the  Syrian  asphalt  is  ex- 
ploited near  Hasbaya,  in  the  Province  of  Damas,  by  the  Civil  List 
of  the  Sultan.  The  mineral  is  hard  and  of  a  brilliant  lustre,  with  a 
marked  odor.  It  is  of  great  purity,  and  is,  therefore,  used  entirely 
in  the  manufacture  of  varnishes  and  aniline  dyes.  It  has  been 
chiefly  marketed  at  Trieste,  where  it  is  quoted  at  $84.00  per  ton, 
boxed  and  delivered.  The  demand  is,  however,  limited,  so  that  the 
yearly  output  is  only  a  few  hundred  tons. 

An  Anglo-German  company  with  headquarters  in  Constanti- 
nople, has  been  formed  to  work  other  deposits  in  Palestine,  but 
so  far  they  have  not  obtained  the  concession. 

Bituminous  schists  are  found  near  Beyrout.  Some  movement 
has  been  made  towards  working  them  and  a  large  trial  lot  has 
been  sent  to  England,  but  so  far  there  has  been  no  real  activity. 

Dr.  Edgar  James  Banks,  formerly  American  Consul  at  Bag- 
dad, and  now  director  of  the  Urarchaeological  Exploring  Expedi- 
tion, states  that  there  are  springs  of  bitumen  opposite  the  town  of 
Nasarieh,  Province  of  Busreh,  about  100  miles  from  the  site  of 
Babylon.  The  deposits  are  near  a  navigable  river,  but  are  not 
exploited,  save  that  the  material  is  to  a  certain  extent  used  by 
the  natives  as  a  cement  in  building,  and  as  a  substitute  for  sealing 
wax. 

In  Amsterdam,  the  writer  went  over  the  works  of  the  Neu- 
chatel  Asphalt  Co.  with  the  resident  manager,  Mr.  J.  Patten 


72  ASPHALTS.  [CHAP.  xi. 

Walsh,  who  pointed  out  one  of  the  recent  improvements  in  the 
laying  of  compressed  asphalt  streets  through  the  use  of  mastic 
adjoining  tramway  rails  and  where  the  asphalt  pavement  came  in 
conjunction  with  pavements  of  other  material.  Repairs  to  the 
asphalt  streets  necessitated  by  gas  leakage  attracted  attention  as 
in  streets  laid  ten  years  there  were  no  other  defects. 

A  report  on  this  subject  by  Dr.  James  C.  Bayles,  M.  E.,  at 
a  Convention  of  the  League  of  American  Municipalities  is  in- 
teresting in  this  connection.  Dr.  Bayles  says  that  in  case  of 
asphalt,  the  destruction  due  to  gas  leakage  is  rapid  and  complete. 
The  first  surface  indication  is  a  depression  marked  with  parallel 
striations  in  the  direction  of  the  movement  of  traffic.  This  indi- 
cates that  the  binder  has  been  decomposed,  allowing  the  super- 
ficial layer  to  yield  under  the  wheels  of  vehicles.  A  bar  hole  put 
down  through  such  a  spot  will  always  find  a  gas  leak.  Gas  may 
also  be  found  in  large  quantities  under  sound  asphalt — a  phenom- 
enon which  has  given  rise  to  some  confusion. 

The  explanation  is  really  very  simple.  What  rots  the  binder 
of  the  asphalt  pavement  is  neither  the  hydrogen  nor  the  carbon 
monoxide.  In  fact,  uncarburetted  water  gas  would  not  touch  it. 
The  mischief  is  done  by  the  naphtha  enrichments  composing  the 
olefiant  series.  These  are  high  solvents  of  everything  bituminous. 
Gas  which  leaks  from  a  buried  pipe  works  its  way  upward  until  it 
strikes  the  binder  of  the  asphalt.  This  is  attacked  by  the  olefiants, 
and  decomposed.  The  gas,  returned  to  the  composition  of  uncar- 
buretted water  gas  and  inert,  so  far  as  asphalt  is  concerned,  works 
its  way  in  all  directions  until  it  finds  some  avenue  of  escape. 

One  of  the  largest  industries  in  connection  with  bitumen  is 
the  manufacture  and  application  of  bitumen  damp  course  and 
sheeting  and  the  laying  of  conduits  with  bitumen.  The  writer 
met  Mr.  Thomas  Callender,  Chairman  of  the  Board  of  Directors 
of  Callender's  Cable  and  Construction  Co.,  in  London,  and  was 
surprised  to  hear  that  the  company  had  at  that  time  seven  thou- 
sand men  at  work  in  their  large  factory  at  Belvedere  and  on  the 
work  they  were  constructing. 

Mr.  George  M.  Callender  called  attention  to  an  opinion  given 
by  Mr.  Allan  Greenwell,  A.  M.,  I.  C.  E.,  who  prefaced  his  views 
with  the  statement :  "  'The  art  of  directing  the  great  sources  of 
power  in  nature  for  the  use  and  convenience  of  man'  is  the  apt 
definition  given  by  the  late  Thomas  Telford  of  that  species  of 


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'A  S  P  H  A  L  T  S' 


TURKISH    AND    OTHER    BITUMENS.  73 

knowledge  which  constitutes  the  profession  of  a  civil  engineer,  and 
is  perpetuated  in  the  Charter  of  the  Institution  of  Civil  Engineers. 
In  the  acquisition  of  this  knowledge  the  civil  engineer  has  to  make 
himself  acquainted  with  the  various  physical  properties,  possessed 
in  varying  degrees  by  the  different  forms  of  matter.'" 

Mr.  Greenwell  further  states  that  asphaltic  materials  are  now 
being  largely  used  in  order  to  render  works  impervious  to  water. 
They  possess  the  advantage  of  small  relative  bulk,  ease  and 
rapidity  in  laying,  and  claim  to  possess  sufficient  elasticity  in 
order  to  accommodate  themselves  to  slight  alterations  in  the 
shape  or  condition  of  structures  due  to  the  subsidence,  expansion 
or  contraction  or  other  causes. 

In  considering  these  materials  a  distinction  must  be  drawn  be- 
tween : 

(a)  Pure  asphalt  or  bitumen. 

(b)  Rock  asphalt  or  bitumen  and  calcareous  rock. 

(c)  Artificial  asphalt,  manufactured  with  coal  products. 

Artificial  asphalt  has  been  introduced  to  the  engineering  pro- 
fession under  many  forms,  but  each  form  in  turn  has  proved  to  be 
unreliable,  absence  of  elasticity  resulting  in  fracture  and  fissuring, 
being  its  constant  defect.  The  unfortunate  popular  lack  of  knowl- 
edge as  to  the  real  nature  of  bitumen,  and  its  essential  difference 
from  artificial  or  so-called  tar  asphalt  has,  however  frequently  per- 
mitted the  substitution  of  the  latter  for  the  former  causing  incal- 
culable detriment  to  the  proper  appreciation  of  the  pure  substance. 

Rock  asphalt  although  a  natural  substance  containing  pure 
bitumen,  is  also  wanting  in  elasticity,  and  is  therefore  not  adapted 
for  works  where  imperviousness  to  water  under  all  circumstances 
is  a  sine  qua  non. 

Pure  bitumen  appears  to  possess  those  qualities,  including 
elasticity,  which  are  requisite  in  a  perfect  waterproofing  material 
for  use  in  engineering  works,  and  experience  of  its  use  under  most 
trying  circumstances  leads  to  the  conclusion  that  it  may  be  classed 
as  an  absolutely  reliable  material,  for  which  a  great  future  may  be 
safely  predicted. 

In  Mexico  there  are  nummerous  deposits  of  asphalt  princi- 
pally of  the  maltha  or  liquid  grade ;  it  has  been  found  in  numerous 
deposits  from  the  Panuco  River  to  the  Isthmus  of  Tehuantepec. 
While  a  few  hundred  tons  of  this  material  have  been  shipped  to 
the  United  States,  the  expense  of  getting  it  here  has  been  so  great 


74  ASPHALTS.  [CHAP.  xi. 

that  its  use  has  been  abandoned.  From  this  country,  also,  comes 
the  Chapopota  asphalt  used  for  varnishes  but  generally  superseded 
in  use  by  less  expensive  asphalts  of  a  similar  nature. 

In  the  last  report  of  the  U.  S.  Geological  Survey  an  occur- 
rence of  bitumen  was  reported  in  Oklahoma  about  3  miles  south- 
east of  Fort  Sill.  From  recent  information  received  from  Captain 
Farrand  Sayre,  U.  S.  Cavalry,  then  stationed  there,  the  deposit 
is  known  as  "Tar  Spring,"  a  black  substance  oozes  out  from  the 
ground  which  is  now  believed  to  be  petroleum.  A  well  has  been 
bored  near  it  in  the  hope  of  finding  mineral  oil,  and  natural  gas 
has  geen  found.  No  bituminous  limestones  or  sandstones  are 
known  to  be  in  the  region. 

The  latest  commercial  development  of  asphalt  is  the  refinery 
of  the  United  States  and  Venezuela  Co.  erected  near  Maracaibo, 
where  is  refined  the  product  of  an  asphalt  lake  containing  97  acres 
area  of  solid  bitumen.  This  refinery  with  other  improvements  cost 
about  $500,000,  and  large  quantities  of  the  refined  material  have 
already  been  brought  to  this  market.  Professor  Stillman,  of  the 
Stevens  Institute  of  Technology  gives  the  analysis  of  the  asphalt 
as  follows : 

Crude.  Refined. 

Bitumen    94-13  99-°7 

Woody  fibre,  etc 4.85  0.25 

Ash  i  .02  0.68 


100.00  100.00 

and  adds  "The  Refined  Asphalt  is  of  very  superior  quality."  Ralph 
T.  Rokeby,  the  President  of  the  company,  evolved  the  idea  of  fill- 
ing the  refined  asphalt  into  bags  which  has  proved  a  wise  innova- 
tion, as  the  saving  in  cost  of  the  weight  of  these  packages  as 
against  the  heavy  wooden  barrels  generally  used  is  a  great  benefit 
to  the  purchasers.* 

*  Author's  Note:   Owing  to  troubles  with  the  Venezuelan  Government  it  has 
been  impossible  for  the  last  three  years  to  import  this  material  from  Maracaibo. 


CHAPTER  XII. 

DEVELOPMENTS  OF  THE  ASPHALT  INDUSTRY  UP  TO 

1903. 

DEVELOPMENTS  of  the  Asphalt  Industry  up  to  1903  were 
so  ably  treated  on  before  the  Institution  of  Civil  Engineers 
in  London,  by  his  long  tiem  friend  and  coadjutor,  William  Henry 
Delano,  of  the  Val  de  Travers  Asphalte  Paving  Co.,  that  the 
author  has  given  his  paper,  "Recent  Developments  of  the  Asphalt 
Industry,"  verbatim. 

"Since  1880,  when  a  paper*  by  the  author  on  "The  Use  of 
Asphalt  and  Mineral  Bitumen  in  Engineering,"  was  read  before  a 
meeting  of  the  Institution,  the  employment  of  the  material  has  so 
largely  increased  that  it  may  be  worth  while  to  take  a  retrospec- 
tive view,  and  a  glance  into  the  future  of  this  industry,  in  which 
so  much  British  capital  is  invested,  and  the  development  of  which 
gives  employment  to  so  many  engineers. 

"Asphalt  is  a  natural  product,  and  consists  of  limestone  im- 
pregnated with  pure  mineral  bitumen.  Its  ideal  composition  is 
80  per  cent,  to  90  per  cent,  of  pure  carbonate  of  lime,  and  10  per 
cent,  to  20  per  cent,  of  pure  mineral  bitumen.  Bitumen  is  natural 
mineral  pitch,  composed  of  85  per  cent,  of  carbon,  12  per  cent,  of 
hydrogen  and  3  per  cent,  of  oxygen.  It  is  only  found  pure  in  the 
rock  which  it  permeated  when  in  a  state  of  vapor,  and  under  enor- 
mous pressure.  The  recent  eruption  of  Mount  Pelee,  in  Martin- 
ique, affords  evidence  of  the  great  heat  and  pressure  caused  by  the 
combustion  of  bituminous  vapors.  Mineral  bitumen  should  not  be 
confounded  with  the  residuum  of  crude  petroleum,  naphtha,  shale, 
or  animal  fats,  nor,  above  all,  with  gas-tars :  these  contani  dyes, 
which  natural  bitumen  does  not.  As  asphalt  and  bitumen  are 


*Read    before    the    Institution    of    Civil    Engineers,  London,  Eng.  Ses- 
sions 1902-1903. 


76  ASPHALTS.  [CHAP.  xn. 

natural  products,  they  vary  in  quality  and  must  be  taken  as  Nature 
produces  them.  Thus  the  limestone  in  the  Sicilian  variety  of 
asphalt  is  of  coarse  grain;  but  in  Seyssel,  Val  de  Travers  and 
Servas  asphalts  the  grain  is  fine,  so  that  the  specific  gravity  of 
Sicilian  asphalt  is  less  than  that  of  the  other  rocks  named.  The 
bitumen  contained  in  Seyssel  and  Sicilian  asphalts  is  solid  and 
tough,  whereas  that  contained  in  Val  de  Travers  asphalt  is  oily. 

"The  author  having  experienced  much  trouble  due  to  waves 
and  buckling  in  roadways  of  Val  de  Travers  asphalt  under  heavy 
traffic  and  exposure  to  hot  suns,  consulted  the  later  Mr.  Schiitzen- 
berger,  Professor  of  Chemistry  at  the  College  de  France,  who  had 
made  a  special  study  of  hydro-carbons.  This  eminent  chemist, 
after  separating  the  bitumen  from  the  pulverized  rock  by  dissolv- 
ing it  in  carbon  di-sulphide  and  filtering  the  solution,  heated  the 
bitumen  in  vacuo  without  obtaining  any  appreciable  evaporation; 
when  the  heat  was  increased  the  bitumen  decomposed.  This 
showed  that  the  oil  could  not  be  got  rid  of  by  heat,  and  led  the 
author  to  blend  Seyssel  with  Val  de  Travers,  and  subsequently  with 
Servas  rock,  with  satisfactory  results.  By  blending,  asphalt  pow- 
der for  roadways  can  be  obtained  suitable  for  tropical  or  temperate 
climates. 

"The  molecules  of  natural  asphalt  are  held  together,  not  by 
cohesion,  but  by  bituminous  agglutination.  Mr.  Leon  Malo  found 
that  the  test  for  asphalt  is  to  heat  a  small  piece  on  a  hot  iron 
plate,  when  it  will  fall  to  pieces.  To  test  its  compressibility,  a  small 
hydraulic  press  with  appropriate  molds,  or  a  tube  with  a  plug  and 
hammer,  may  be  used.  Some  asphalts,  after  being  subjected  to  a 
pressure  of  6  tons  per  square  inch,  will  crumble  under  pressure  of 
the  fingers.  The  unimpregnated  limestone  found  in  an  asphalt 
mine  will  not  crumble  on  being  heated. 

"Asphalt  mastic  is  composed  of  asphalt  powder  and  refined 
bitumen,  mixed  mechanically  in  a  boiler  under  heat.  The  mixture, 
after  being  heated  to,  say,  400°  F.,  is  run  into  molds,  the  blocks 
weighing  about  56  pounds.  It  should  contain  about  15  per  cent,  of 
bitumen,  native  and  added,  and  will  not  fall  to  pieces  on  being 
heated,  as  asphalt  rock  does,  nor  will  it  compress.  Mr.  Malo  has 
pointed  out  that  in  a  layer  of  compressed  asphalt  the  top  of  the 
layer  is  always  denser  than  the  bottom,  even  when  the  thickness 
has  been  reduced  by  wear  to  ^  inch.  The  surface,  therefore, 
always  rests  on  a  cushion.  To  make  good  mastic,  care  and  expert- 


"ASPHALT  S' 


ASPHALT   INDUSTRY    TO    1903.  77 

ence  are  required.  It  must  be  made  of  blended  rocks,  ground  very 
fine,  mixed  with  refined  bitumen  and  thoroughly  cooked ;  it  cannot 
be  too  pure.  For  footpaths,  grit  is  added  to  it,  say,  33  per  cent, 
for  temperate,  and  50  per  cent,  for  tropical  climates.  Clay,  pyrites 
and  vegetable  matter  are  all  detrimental,  whilst  taking  up  the  place 
of  good  material.  The  qualities  of  asphalt,  bitumen,  and  their 
product,  mastic,  are  remarkable,  and  are  daily  being  more  and 
more  appreciated  in  engineering  work. 

"Asphalt  makes  noiseless  roadways,  is  impervious  to  water, 
and  produces  no  dust  or  mud ;  mastic  makes  footpaths  like  a  car- 
pet, arrests  capillarity,  is  air-,  water-  and  vermin-proof,  absorbs1 
vibration  and  is  a  non-conductor  of  electricity.  By  mixing  bitu- 
men with  pure  silex,  a  mastic  can  be  made  which  resists  acids. 

"The  Island  of  Sicily  alone  now  produces  annually  75,000  tons 
of  natural  asphalt,  sufficient  to  lay  812,000  square  yards  of  com- 
pressed asphalt,  2  inches  in  thickness;  whilst  the  output  of  the 
other  mines  in  Europe  (Seyssel,  Val  de  Travers,  Chieti  in  the 
Abruzzi,  Limmer,  Vorwohle,  Lobsann,  Auvergne  and  Syzrane  in 
Russia)  may  be  estimated  at  120,000  tons  annually;  whereas  pre- 
viously to  1870  the  Seyssel  and  Val  de  Travers  mines  were  the 
only  ones  of  repute,  and  their  combined  annual  output  was  about 
50,000  tons.  When  in  the  United  States  some  five  years  ago,  the 
author  noticed  that  one  American  Company,  managed  by  a  Col- 
onel of  Engineers,  had  an  army  of  18,000  men  employed  daily  in 
laying  bituminous  compounds  for  roadways  in  different  towns  of 
the  Union.  Often  the  process  followed  was  to  construct  the  roads 
first,  and  to  build  the  towns  afterwards ;  where  money  was  not 
available,  payments  were  effected  in  bonds  on  land,  or  even  on 
produce.  The  author's  experience  has  been  acquired  chiefly  in 
France,  where  the  asphalt  industry  originated,  and  where  the 
special  plant  and  tools,  now  used  everywhere,  were  invented  and 
elaborated. 

"In  1872  the  author  was  called  upon  to  undertake  the  man- 
agement of  the  original  Asphalt  Company,  which  had  the  contract 
for  all  the  compressed  asphalt  roadways  for  the  town  of  Paris. 
These  roadways  were  then  being  laid  on  hydraulic-lime  concrete, 
only  4  inches  in  thickness — actually  the  same  thickness  as  for 
footpaths — and  of  this  y2  inch  thickness  consisted  of  a  mortar 
floating,  spread  upon  the  concrete  after  it  had  been  laid,  which 
crumbled  under  the  blows  of  the  rammers  used  in  ramming  the 


78  ASPHALTS.  [CHAP.  xn. 

hot  asphalt-powder  to  make  the  road.  On  the  author's  recom- 
mendation, Portland-cement  concrete  was  laid,  at  the  company's 
expense,  in  the  Rue  d'Antin,  and  this  work  stands  to  the  present 
day ;  the  old  streets,  however,  were  all  laid  on  lime  concrete.  Some 
of  the  engineers  of  the  town  of  Paris  who  had  the  superitnndence. 
of  the  works  declined  to  have  Portland-cement  concrete  at  any 
cost,  and  at  the  end  of  five  years,  when  the  concrete  wore  out,  the 
company  had  lost  £40,000,  owing  to  the  onerous  conditions  of  the 
maintenance  contract,  by  which  they  were  paid  I  franc  per  square 
metre  per  annum  for  all  repairs,  including  the  relaying  of  one- 
tenth  of  the  surface  annually  and  setting  the  whole  in  order  at 
the  end  of  the  contract.  When  holes  in  the  asphalt  had  to  be 
repaired,  the  crumbling  concrete  had  to  be  relaid  also,  but,  owing 
to  the  exigencies  of  traffic,  it  had  not  sufficient  time  to  set,  so  that 
work  was  carried  out  under  grave  difficulties ;  and  in  rainy 
weather,  in  order  to  get  a  dry  surface  for  the  hot  powder,  it  was 
necessary  to  use  bituminous  concrete,  or  at  least  a  layer  of  liquid 
asphalt. 

"In  general,  yielding  materials  like  asphalt  require  a  rigid  and 
resisting  concrete,  and  floating  is  undesirable.  Finding  how  detri- 
mental to  the  asphalt  roads  was  the  greasy  mud  brought  from 
macadam  and  stonepitching,  the  author  presented  the  town  of 
Paris  with  one  hundred  india  rubber  squeegees,  and  this  led  to  the 
adoption  and  manufacture  of  these  tools  in  France.  He  also  de- 
signed a  special  form  of  water  cart  for  cleaning  asphalt  roadways, 
the  sprinkling  being  effected  in  front  of  the  horses,  sa  well  as  be- 
hind them,  the  French  plan  of  flushing  with  a  fireman's  hose  and 
nozzle  being  impracticable  in  narrow  streets  or  in  windy  weather. 
The  extreme  gradient  for  an  asphalt  roadway  is  I  in  30,  and  the 
camber  between  the  outside  edge  of  the  gutter  and  the  crown  of 
the  road  should  not  present  gradients  of  more  than  I  in  50. 

"In  1884  the  town  of  Paris  made  a  lo-years'  contract  with  the 
author's  company,  by  which  they  agreed  to  pay,  for  a  2-inch  layer 
of  compressed  asphalt,  14  francs  per  square  metre  (gs.  4d.  per 
square  yard)  and  for  a  6-inch  layer  of  Portland-cement  concrete 
5^  francs  per  square  metre  (35.  8d.  per  square  yard),  and  for 
maintenance  2  francs  per  square  metre  (is.  4d.  per  square  yard) 
per  annum,  with  the  undertaking  that  all  the  streets  laid  with  lime 
concretes  should  be  relaid  with  Portland-cement  concrete,  the 
town  paying  for  the  repairs  on  those  streets  apart,  until  the  sub- 


ASPHALT    INDUSTRY    TO    1903.  79 

stitution  should  take  place.  It  was  in  1884  that  Sicilian  asphalt 
was  accepted  for  the  first  time,  the  Paris  engineers  having  been 
commissioned  to  visit  and  report  on  every  asphalt  mine  then 
known,  and  it  took  the  place  of  St.  Jean  de  Marvejols  asphalt, 
being  cheaper.  A  branch  of  the  London  Limmer  Asphalt  Com- 
pany obtained  the  contract  for  about  one-third  of  Paris,  but  after- 
wards passed  over  their  contract  to  a  French  company,  formed  by 
the  Neuchatel  Company,  Limited,  which  holds  the  concession  for 
the  Val  de  Travers  mines,  who  had  not  renewed  their  concession 
to  the  author's  company.  It  is  notable  that  English  capital  had 
absorbed  the  asphalt  industry  originated  in  France,  and  led  to  its 
development  all  over  the  world. 

"The  town  of  Paris  allowed  the  contractor  to  grind  up  the 
pieces  of  old  compressed  asphalt  from  gas  trenches  and  repairs, 
and  to  convert  it  into  mastic  for  the  liquid  gritted  asphalt  foot- 
paths ;  but  it  would  not  allow  the  old  gritted  mastic  from  the  foot- 
paths to  be  used  again  for  new  works  or  relayings ;  this  could  only 
be  used  for  small  repairs  and  trenches,  and  even  then  only  if  mixed 
with  an  equal  quantity  of  new  material.  The  area  of  the  asphalt 
mastic  footpaths  in  Paris  is  about  6,000,000  square  yards;  this 
material  provides  a  surface  which  is  less  fatiguing  to  walk  on,  and 
much  more  agreeable  to  the  sensitive  human  foot,  than  granite, 
stone,  or  hard  cement.  The  town  paid  35  centimes  per  square 
metre  (2.8d.  per  square  yard)  per  annum  for  the  maintenance  of 
the  footpaths,  laid  15  millimetres  (9/16  inch)  in  thickness,  for  all 
repairs  arising  from  wear  and  tear,  including  the  re-laying  of  one- 
fifteenth  part  of  the  entire  surface  every  year,  whether  wanted  or 
not.  The  thickness  of  the  layer  being  15  millimetres,  and  the  wear 
of  the  surface  of  the  surface  being  estimated  at  I  millimetre  per 
annum,  it  was  supposed  that  at  the  end  of  15  years  the  whole  sur- 
face would  be  re-laid.  In  practice,  howeve,  it  was  found  that  the 
narrow  streets  in  the  centre  of  the  town  wore  out  in  5,  6,  or  10 
years,  owing  to  the  heavy  traffic,  whereas  those  in  the  suburbs 
were  as  good  at  the  end  of  15  years  as  on  the  day  they  were  laid. 
Knowing  that  old  mastic,  remelted  with  fresh  bitumen  (the  main 
ingredient  of  asphalt),  is  just  as  good  as,  if  not  better  than,  new 
mastic,  owing  to  the  second  fusion,  the  author  proposed  to  lay  all 
surfaces  20  millimetres  (£4  inch)  thick,  instead  of  15  millimetres 
(9/i6inch), using  a  mixture  of  equal  quantities  of  old  and  new  mas- 
tic, already  admitted  for  repairs  and  trenches,  and  to  suppress  the 


8o  ASPHALTS.  [CHAP.  xn. 

obligation  to  re-lay  one  fifteenth  part  of  the  surface  annually,  only 
re-laying  what  was  necessary,  thus  saving  annoyance  to  house- 
holders and  unnecessary  carting,  whilst  the  contractor  got  rid  of 
materials  easily  that  otherwise  he  had  to  sell  to  suburban  corpora- 
tions, private  undertakings,  etc.  The  proposal  was  agreed  to,  and 
this  arrangement  has  been  continued  ever  since,  to  the  general 
advantage  of  all  concerned.  The  concrete  used  with  compressed 
asphalt  prepared  in  this  way  is  composed  of  washed  flint  pebbles, 
river  sand,  and  best  Portland  cement,  gauged  4,  3  and  I.  The 
cement,  not  more  than  2  months  old,  is  first  turned  over  dry,  then 
mixed  wet,  being  sprinkled  just  enough  to  hydrate  it.  No  floating 
is  required.  A  level  surface  is  obtained  by  using  a  straight-edge 
and  smoothing  the  mass  with  a  flat  rectangular  shovel,  filling  up 
any  cavities  with  a  little  mortar,  composed  of  3  of  sand  and  I  of 
cement,  mixed  on  the  spot.  By  this  plan  the  whole  mass  sets  at 
the  same  time,  which  is  absolutely  necessary  for  hot  asphalt 
powder,  whereas  for  wood  or  cold  asphalt  slabs  this  is  not  neces- 
sary. It  is  well  to  allow  5  days  for  setting  in  summer,  or  7  days 
in  winter,  and  the  surface  must  be  dry,  otherwise  the  powder, 
heated  to  300°  F.,  would  convert  any  moisture  into  steam,  which, 
in  passing  through  the  asphalt,  would  give  rise  to  nodules.  For 
liquid-asphalt  footpaths,  hydraulic-lime  concrete  may  be  used,  and 
a  mortar  floating,  in  order  to  get  a  true  surface  with  a  straight- 
edge, and  to  prevent  more  asphalt  being  laid  than  the  thickness 
warrants.  A  ^4-inch  layer  weighs  80  Ibs.  to  the  square  yard. 

Perhaps  the  best  method  of  protecting  any  work  in  masonry, 
or  iron  vaults,  roofs,  reservoirs,  etc.,  is  by  means  of  two  layers  of 
pure  asphalt,  2/5  inch  in  thickness,  superposed,  the  joints  of  the 
first  layer  being  covered ;  a  recess  can  be  cut  into  the  masonry  and 
the  fillet  pressed  in.  Such  a  layer  will  weigh  about  68  Ibs.  per 
square  yard.  A  damp-course  laid  in  walls  of  buildings,  at  a  level 
of  about  i  foot  above  the  ground,  will  stop  capillarity  and  preserve 
the  buildings  from  the  action  of  water  and  frost.  To  keep  out 
damp  is  as  much  a  necessity  of  hygiene  as  good  drainage.  The 
Egyptian  Sphinx,  the  Pyramids,  and  so  many  tombs  and  buildings, 
not  to  mention  more  recent  Roman  buildings  in  Africa,  have  sur- 
vived mainly  because  the  chief  elements  of  decay,  water  and  frost, 
are  absent ;  if  such  constructions  had  been  in  England,  the  expan- 
sion caused  by  frost  and  the  contraction  caused  by  thaw  would 
speedily  have  disintegrated  them.  In  many  brick  and  stone  rail- 


SI 


19 


"A  S  PH  ALT  S' 


ASPHALT    INDUSTRY    TO    1903.  8l 

way  arches  in  Paris,  water  drips  through  the  joints  after  prolonged 
rain.  The  Pont  du  Jour,  a  stone  viaduct  over  the  Seine  at  Auteuil, 
is  full  of  water  in  rainy  weather,  and  from  certain  joints  water  runs 
out  as  from  a  spring.  Mr.  Barabant,  the  Manager  of  the  Eastern 
Railway  of  France,  who,  as  Ordinary  Engineer,  and  subsequently 
as  Chief  Engineer,  of  the  town  of  Paris,  had  special  opportunities 
of  studying  asphalt — having  had  the  Municipal  Laboratory  under 
his  charge — has  had  all  the  "bridges  and  viaducts  on  the  ordinary 
and  strategic  lines  between  Paris  and  the  frontier  laid  with  pure 
asphalt  coating,  and  has  had  the  platforms  of  the  Paris  and  Nancy 
stations  laid  in  compressed  asphalt  slabs  and  powder.  The  Paris, 
Lyons  and  Mediterranean,  Orleans,  Midi,  North  and  West  Rail- 
way Companies  have  largely  used  Seyssel  asphalt  for  platforms, 
bridges,  viaducts,  etc. 

"It  has  been  abundantly  proved  that  asphalt  mastic  is  un- 
affected by  cold  or  heat,  i.  e.,  expansion  and  contraction  do  not 
alter  its  qualities.  The  late  Captain  Coignet  had  some  of  the 
Seyssel  asphalt  coating  from  the  bomb-proof  casemates  of  the 
Donjon  of  Vincennes  taken  up,  after  laying  entombed  since  1833, 
and  found  that  no  change  had  taken  place  in  the  asphalt.  A  root 
of  lucerne,  5  to  6  yards  in  length,  had  tried  in  vain  to  penetrate 
the  layer.  Asphalt  has  the  defects  of  its  qualities,  for  in  foggy 
weather  the  moisture  in  the  atmosphere  will  condense  on  the 
asphalted  surface  of  the  casemates,  and  must  be  swabbed  off.  This 
is  better  than  letting  it  soak  into  an  ordinary  soil.  But,  for  this 
reason,  in  asphalted  railway  stations,  flour,  cement  and  lime  must 
be  kept  off  the  ground  by  wooden  frames.  The  gradual  disinteg- 
ration of  walls  and  floors  is  sometimes  traceable  to  the  ravages 
of  rats  and  mice ;  they  will  nibble  through  concrete,  but  they  leave 
asphalt  alone.  Being  a  non-fermenting  and  non-decaying  mate- 
rial, it  affords  no  home  for  insects.  A  floor  laid  on  joists  fixed  on 
liquid  asphalt  is  safe  from  vermin,  and  there  need  not  be  any 
appreciable  space  between  the  asphalt  coating  and  the  upper  floor- 
ing. In  the  case  of  fire,  asphalt  keeps  out  the  air,  and  holds  water  ; 
when  the  wood-work  below  it  has  been  burned  away,  it  will  fall 
like  a  wet  blanket  on  the  flames  and  extinguish  them.  This  qual- 
ity was  proved  by  the  experiments  made  by  the  Omnibus  and 
Cab  Companies  in  Paris,  with  the  result  that  the  floors  of  gran- 
aries and  silos,  wash-houses,  stables  and  mangers  are  now  gen- 
•erally  coated  with  liquid  asphalt.  It  was  found  by  Messrs.  Tourtel 


82  ASPHALTS.  [CHAP.  xn. 

Freres,  of  Tantonville,  near  Nancy,  that  whereas  gas  tar  gave  a 
disagreeable  flavor  to  malt,  natural  asphalt  was  absolutely  neutral ; 
this  has  led  to  its  adoption  for  flooring  in  many  breweries  and 
makings.  Slabs  of  asphalt  of  various  sizes  and  thicknesses,  made 
made  in  a  hydraulic  press,  are  now  manufactured  largely  and  sent 
to  all  parts  of  the  world.  They  are  laid  on  Portland-cement  con- 
crete similarly  to  asphalt  power,  but  are  fixed  in  a  wet  layer  of 
pure  Portland-cement  mortar;  after  being  laid,  cement  grout  is 
poured  into  the  scarcely  perceptible  joints,  and  swept  off  with  saw- 
dust when  dry.  These  slabs  stand  well  in  streets  and  courtyards 
where  there  is  little  traffic,  and  require  no  costly  plant,  as  does 
powder;  they  can  be  laid  on  wet  concrete,  but,  as  they  have  at- 
tained their  ultimate  compression,  wear  begins  at  once. 

"A  method  of  laying  asphalt  powder  cold,  by  mixing  it  with 
petroleum  essence  and  a  solution  of  india-rubber,  which  softens  the 
bitumen  contained  in  the  rock  and  so  facilitates  compression,  the 
petroleum  afterwards  evaporating,  has  been  recently  employed  in 
Marseilles,  Antibes,  Barcelona,  Aix-les-Bains,  Toulon,  Nice  and 
St.  Etienne.  By  this  process  work  can  be  done  in  rainy  weather. 

"Just  as  plasterers  mix  cow-hair  with  their  plaster,  and  as 
cement  is  strengthened  by  iron  wire  and  rods  to  give  it  tenacity 
under  strain,  so  liquid  asphalt  can  be  treated  for  making  tanks, 
pipes,  conduits,  reservoirs,  etc.  Asphalt,  and  india-rubber,  of 
which  it  is  a  counterpart,  are  both  hydro-carbons,  having  the 
same  ingredients.  Asphalt  has  little  resisting  power  in  itself,  but 
it  can  be  laid  on  a  hempen  sheet  or  thick  paper,  to  give  it  more 
tenacity,  as  when  laid  upon  a  wood  flooring.  When  liquid  asphalt 
is  used  for  the  inside  lining  of  a  reservoir,  vertically,  a  layer  of 
brick  should  be  laid  in  front  of  it  as  the  work  proceeds,  to  keep 
it  up.  In  Germany,  cement  tanks  for  holding  molasses  are  now 
being  replaced  by  asphalt,  which  does  not  crack.  Bitumen  resists 
alkalies  and  acids,  so  that  by  mixing  it  with  pure  silex  in  powder, 
or  with  pulverized  basalt,  a  mastic  or  paste  can  be  made  which 
can  be  applied  like  ordinary  mastic  for  accumulator-rooms,  baths 
for  electrolysis,  etc. ;  numerous  special  applications  of  this  material 
have  been  made  for  the  Electric  Traction  Company  at  Paris, 
Lyons,  and  elsewhere.  It  has  been  found  that  the  large  Portland- 
cement-concrete  blocks  used  in  connection  with  breakwaters  and 
piers  to  arrest  the  force  of  the  waves,  become  disintegrated  by  the 
action  of  the  magnesia  in  the  sea-water,  as  well  as  by  the  boring 


ASPHALT    INDUSTRY    TO    1903.  83 

propensities  of  numerous  marine  animals.  The  blocks  may  be 
protected  by  an  application  of  liquid  asphalt,  say  9-16  inch  thick, 
upon  each  side  of  the  cube,  carefully  jointed  at  the  angles,  and  the 
remedy,  though  expensive,  is  sure.  Asphalt  flags  are  made  by 
running  mastic  in  shallow  moulds  on  a  true-planed  cast-iron  slab ; 
they  are  laid  on  a  concrete  base,  the  joints  being  run  with  a  little 
special  mastic,  heated  in  an  iron  basin  and  spread  with  an  iron 
tool.  At  the  works  of  the  Compagnie  Generale  des  Asphaltes  de 
France,  the  strong-room  is  made  of  bituminous  concrete,  and  is 
absolutely  fireproof.  Pipes  and  tubes  can  be  made  for  the  carry- 
ing of  telegraph,  telephone  or  power-wires.  Bitumen  resists  the 
corrosive  action  of  acetylene-gas  on  iron  pipes;  and  in  Paris, 
water-pipes  are  coated  with  a  layer  of  mastic  before  being  laid  in 
the  ground,  thus  preventing  external  corrosion. 

"The  chief  application  of  asphalt  to  which  the  Author  desires 
to  direct  attention  in  this  Paper,  however,  is  its  use  as  a  material 
for  absorbing  vibration,  either  caused  by  the  passage  of  trains  and 
heavy  vehicles,  or  by  percussion,  like  that  of  the  steam-hammer, 
and  also  as  a  foundation  for  heavy  ordnance  in  forts.  Mr.  Malo, 
at  the  Seyssel  mines,  first  experimented  on  these  materials,  and 
his  lead  has  been  followed  up  by  the  Author.  The  material  used 
may  be  either  bituminous  concrete,  or  asphaltic  powder,  as  used 
for  roadways ;  the  powder,  however,  must  be  rammed  in  successive 
layers  in  a  suitable  case  or  box,  made  of  steel  or  wrought  iron,  to, 
support  and  maintain  it,  and  the  layer,  instead  of  being  2  inches 
thick,  is  8  inches  to  I  foot  in  thickness.  Asphalt  powder  is  used 
chiefly  for  foundations  for  steam-hammers,  the  bed-plate  fitting  on 
to  the  asphaltic  mass.  There  are  numerous  examples  of  its  use, 
and  no  failure  has  been  recorded.  In  the  year  1872  the  Author 
had  at  work  a  Carr  disintegrator,  making  700  revolutions  per 
minute,  for  grinding  rock-asphalt,  the  axles  being  supported  on 
stout  oak  bearings.  The  vibration  transmitted  through  the  soil  was 
such  that  it  was  quite  impossible  to  write  within  600  feet  of  the 
machine.  Being  threatened  with  a  lawsuit,  he  resolved  to  put 
down  bituminous  concrete  foundations  for  the  bearings,  and  to 
surround  the  pit  in  which  the  machine  worked  by  a  wall  of  the 
same  material.  When  the  work  was  completed,  no  one  could  tell 
in  the  adjoining  workshops  and  warehouses  whether  the  machine 
was  working  or  not,  and  a  glass  of  water  placed  on  the  bituminous 
concrete  wall  showed  no  ripples.  For  30  years,  during  which  at 


34  ASPHALTS.  [CHAP.  xn. 

least  5,000,000  tons  of  asphalt  have  een  ground  to  fine  powder, 
no  repairs  have  been  necessary.  One  of  the  more  notable  applica- 
tions was  made  by  the  Orleans  Railway  in  their  underground 
railway  between  the  Place  Denfert-Rochereau  and  the  Port  Royal, 
where  the  line  oassed  by  the  Paris  Observatory.  Admiral  Mou- 
chez,  who  was  then  Chief  of  the  Observatory,  feared  that  his  mer- 
cury bath  for  daylight  observations  would  be  shaken,  and  a  foun- 
dation consisting  of  633  cubic  yards  of  bituminous  concrete  was 
therefore  laid  under  the  rails  in  1894.  The  trains  have  run  over 
it  ever  since,  and  no  repairs  have  been  found  necessary.  In  the 
premises  of  the  famous  firm  of  Moe't  &  Chandon,  who  keep  a 
stock  of  8,ooo,oot>  bottles  of  champagne  in  the  cellars,  it  was 
feared  that  the  machinery  laid  down  for  the  electric  lighting  of 
their  8  miles  of  cellaring,  would  shake  the  wine,  and  in  1888  the 
author  put  down  21  cubic  yards  of  bituminous  concrete,  with  a 
most  satisfactory  result.  In  1892,  the  machinery  being  increased, 
the  author  laid  down  an  additional  17  cubic  yards.  In  the  au- 
thor's opinion,  the  vibration  on  the  Central  London  Railway 
would  be  absolutely  arrested  by  laying  the  rails  on  a  foundation 
of  bituminous  concrete.  Of  course,  the  train  service  would  have 
to  be  stopped,  but  a  great  deal  might  be  done  in  the  night  at  bad 
places. 

"For  iron  bridges  over  which,  or  under  which,  trains  pass, 
this  material  is  invaluable.  Where  a  Portland-cement  concrete 
will  crack  like  mosaic,  this  material  will  stand.  The  author  has 
proved  this  in  many  cases,  notably  at  an  iron  tubular  bridge  over 
the  Seine  at  Elbeuf;  at  the  Pont  de  1'Aqueduc,  in  Paris;  and  at 
the  railway  bridge  over  the  Ceinture,  or  Girdle  Railway,  at  Cour- 
celles.  At  many  forts  around  the'  French  coast  the  very  heavy 
pivot-guns  are  mounted  on  foundations  of  bituminous  concrete, 
which  absorbs  the  vibration  produced  by  a  heavy  discharge.  The 
author  has  also  used  a  coating  of  asphalt  mastic  in  the  granite 
embrasures  of  forts  to  counteract  the  splintering  caused  by  the 
impact  of  small  shells. 

"During  the  Commune  of  Paris,  in  1871,  the  works  of  the 
author's  company  at  the  Quai  de  Valmy  were  under  fire,  and  bul- 
lets which  struck  a  heap  of  asphalt  powder  were  flattened  out. 
This  led  to  the  coating  of  iron  turrets  with  asphalt.  The  late 
General  Boulanger,  when  Minister  of  War,  arranged  with  the 
author  to  build  a  block  of  390  cubic  yards  of  bituminous  concrete 


WORTHING,    ENGLAND. 


HOVE.   ENGLAND. 
SURFACED   WITH    SEYSSEL    ROCK   ASPHALT    MACADAM. 


20 


"A  S  P  H  A  LT  S' 


ASPHALT    INDUSTRY    TO    1903.  85 

at  the  Polygon  of  Bourges,  to  test  the  effect  of  melinite  shell, 
similar  blocks  being  made  of  Portland-cement  concrete  and  hy- 
draulic lime  concrete.  The  whole  was  surrounded  by  a  wall  of 
unmortared  stones.  Melinite  shells,  4  feet  3  inches  in  length  by 
I  foot  i  £4  inches  in  diameter,  with,  chrome-steel  points,  were  fired 
at  these  masses.  The  result  was  that  the  cement-  and  lime-con- 
crete blocks  were  pulverized ;  the  bituminous  concrete  was  not 
pulverized,  but  was  torn  asunder. 

"The  chief  asphalt  mine  in  Europe  is  the  Seyssel  mine,  the 
largest  in  France.  It  stretches  from  Seyssel  to  Bellegarde  in  the 
synclinal  basin  of  the  Rhone,  which  flows  through  the  Depart- 
ment Ain  on  the  east,  and  the  Haute  Savoie  on  the  west.  It  is 
10  miles  in  length  and  a  little  more  than  3  miles  in  width,  and  its 
superficial  area  is  about  20  square  miles. 

"The  bitumen  which  binds  the  soft  lime  oolite  in  this  mine  to 
form  asphalt  must  have  impregnated  the  limestone  in  a  state  of 
vapor,  as  is  proved  by  the  smoky  appearance  in  the  unimpreg- 
nated  rock  at  Seyssel.  The  occurrence  of  bitumen  in  Trinidad, 
Venezuela,  Cuba,  and  Mexico,  on  the  surface  of  the  earth,  in  its 
viscous  state,  just  as  it  can  be  extracted  from  asphalt  rock,  would 
therefore  appear  to  be  due  to  the  bituminous  vapors  having,  at 
some  depth,  met  with  some  porous  rock  like  sandstone,  through 
which  they  filtered  upwards. 

"In  Europe,  the  country  that  has  taken  the  lead  in  laying 
compressed  asphalt  undoubtedly  is  Germany.  There  is  more- 
compressed  asphalt  paving  in  Berlin  than  in  England  and  France- 
together,  there  being  about  2.y2  million  square  yards,  all  laid  onj 
Portland-cement  concrete,  8  inches  in  thickness.  These  magnifi- 
cent roadways  are  one  of  the  features  of  Berlin,  and  give  it  an 
aspect  of  brightness  and  cleanliness  unknown  to  other  European 
towns.  The  Germans  have  studied  asphalt  synthetically,  and 
have  produced  sundry  imitations.  An  artificial  asphalt,  composed 
of  limestone  and  bitumen,  introduced  by  Professor  Dietrich,  of 
Berlin,  was  laid  in  Konig-strasse,  Berlin,  but  was  afterwards  re- 
placed; a  mixture  of  Vorwohle  asphalt  and  bitumen  is  used  to  a 
considerable  extent.  These  mixtures  are,  perhaps,  cheaper  than 
natural  asphalt,  since,  being  made  on  the  spot,  the  cost  of  railway 
carriage  from  the  mines  is  eliminated;  but  they  are  inferior  to 
natural  asphalt,  and  with  heavy  traffic  the  surface  has  to  be  fre- 
quently repaired.  German  contractors  have  followed  the  English 


86  ASPHALTS.  [CHAP.  xn. 

lead,  and  have  bought  mines  in  Chieti  in  the  Abruzzi,  in  Italy, 
and  in  Venezuela. 

"In  conclusion,  the  author  is  of  opinion  that  English  munici- 
palities can  borrow  money  so  cheaply  that  it  is  not  worth  while 
to  forego  the  advantages  of  hygienic  streets,  in  asphalt,  liquid 
and  compressed." 


CHAPTER  XIII. 
ASPHALTS  IN  1908. 

ABOUT  five  years  have  elapsed  since  the  foregoing  chapters 
were  published*.  During  this  semi-decade  the  increase  in 
the  asphalt  sources  of  production  has  grown  by  leaps  and  bounds. 
Their  utilization  has  also  found  numerous  new  channels  in  the 
latest  construction  improvements  of  this  twentieth  century.  Un- 
questionably the  most  important  development  is  in  the  Texas 
asphalt  refineries.  In  1905  the  author  wrote  for  "Mineral  Indus- 
try," Vol.  13,  published  by  the  Mining  and  Engineering  Journal, 
as  follows : 

"In  1903  considerable  strides  were  made  towards  bringing 
Texas  maltha  and  asphalts  into  prominence,  and  in  1904  the  pro- 
duction was  certainly  more  than  that  of  California  in  1902.  The 
Texas  asphalts  are  the  residuum  of  heavy  asphalt  oils,  similar  in 
character  to  the  California  malthas,  but  with  slightly  different 
chemical  properties.  These  asphalts  have  not  been  used  for  pav- 
ing without  mixture  with  other  asphalts,  and  have  therefore  not 
attracted  the  attention  given  to  California  products.  It  is  said, 
however,  that  Texas  maltha  has  very  generally  taken  the  place  of 
California  maltha  as  the  fluxing  material  used  with  the  harder 
asphalts  for  sheet  asphalt  pavements  throughout  the  country  east 
of  the  Mississippi  River.  This  maltha  has  been  extensively  used 
in  manufacturing  artificial  bitumens,  and  it  has  been  used  in  con- 
junction with  Cuban  hard  asphalt,  Trinidad  manjak,  gilsonite  and 
other  asphalts  requiring  large  amounts  of  softening  material  to 
give  them  pliability. 

The  production  in  1904  has  been  estimated  at  from  25,000  to 
30,000  tons.  A  large  refinery  was  operated  at  Marcus  Hook, 
near  Philadelphia,  but  exact  statistics  of  production  there  and  in 
Texas  are  not  available." 

*They  appeared  in  a  series  of  twelve  monthly  issues  in  the  "Architects 
and  Builders  Magazine." 


ASPHALTS. 


[CHAP.  xin. 


The  trouble  then  experienced  in  obtaining  full  data  on  this 
subject  continues  to  exist,  but  from  the  fact  that  the  Gulf  Re- 
fining Co.  produced  in  1907  over  25,000  tons  one  gets  the  most 
astonishing  fact,  that  should  the  production  of  the  Texas  Co. 
and  the  Sun  Co.  have  been  in  the  same  ratio,  the  result  would  be 
about  75,000  tons  of  material,  which,  on  a  basis  of  99  per  cent, 
pure  bitumen,  would  equal  150,000  tons  of  crude  Trinidad  asphalt, 
that  material  losing  30  per  cent,  in  refining  and  the  refined  ma- 
terial yielding  only  about  54  per  cent,  of  bitumen. 

The  methods  of  refining  appear  to  be  different  among  the 
companies  named.  The  "Texaco"  for  instance,  shows  in  the 
penetration  test  the  following  comparisons  with  other  well-known 
asphalts : 


J 

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MECHANICAL  ANALYSES  ;- 

SHOWING    THE     STABILITY    OF    STANDARD 
ASPHALTIC     CEMENTS 
GIVING     THE     SOFTNESS    (PENETRATION) 
AT    ATMOSPHERIC     TEMPERATURES 

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The  refining  of  Boorman's  Noflux  asphalt  yields  a  material 
giving  practically  the  same  results  in  the  penetration.  This  ma- 
terial is  sold  for  fluxing  European  rock  asphalt  mastics  and  for 
use  in  Malthalithic  sidewalks  and  roads,  as  well  as  in  the  standard 
sheet  asphalt  pavements. 


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'A  S  P  H  A  L  T  S' 


ASPHALTS    IN    1908.  89 

The  uses  to  which  these  asphalts  have  been  put  are  varied, 
and  to  a  great  extent,  they  have  been  used  for  blending  with  hard 
or  glance  pitch  asphalts  for  different  classes  of  work,  and  exten- 
sively for  water  proofing  and  insulating  and  in  the  manufacture 
of  roofing  felts  and  prepared  roofings.  One  of  the  latest  applica- 
tions of  this  material  seen  by  the  writer  was  in  the  laying  of  the 
pavement  of  Springdale  Ave.,  between  Roseville  Ave.  and  I3th 
St.,  Newark,  N.  J.,  where  a  two  and  one-half  inch  asphalt  con- 
crete of  Texaco  asphalt  was  applied  on  a  6-inch  Portland-cement 
concrete  base  with  gratifying  results. 

The  Texas  liquid  asphalts  have  entered  largely  in  what  is 
termed  "blended  asphalts,"  one  of  which  is  the  Dunderberg  as- 
phalt, a  blending  of  Trinidad  manjak  or  glance  pitch  with  liquid 
Texas,  the  Dunderberg  Asphalt  Co.  of  New  York  having  a  plant 
at  Jones'  Point,  on  the  Hudson,  where  the  material  is  refined. 
The  Barber  Asphalt  Paving  Co.  also  manufacture  the  "blended 
asphalts,"  and  other  companies  refine  hard  asphalts  on  similar 
lines. 

Among  the  best  qualities  of  California  asphalt  is  that  refined 
for  the  Warren  Asphalt  Paving  Co.,  known  as  Acme  Asphalt. 
The  specifications  read  as  follows: 

"Acme"  Asphalt  Paving  Cement. — The  cementing  material, 
or  paving  cement,  shall  be  prepared  from  the  best  quality  of  pure 
"Acme"  refined  asphaltum  mixed  and  thoroughly  agitated  with 
"Acme"  asphalt  flux  and  unmixed  with  any  of  the  products  of 
coal  tar  or  inferior  bituminous  products. 

The  asphalt  must  be  absolutely  unaffected  by  water  and  suc- 
cessuflly  withstand  the  following  tests : 

(a)  Paint  a  glass  slid  ewith  a  very  thin  film  of  the  asphalt 
cement. 

(b)  Make  a  briquette  of  sand  heated  to  about  250  degrees 
Fahrenheit,  all  of  which  will  pass  a  No.  20  and  none  pass  a  No.  30 
screen,   mixed  with  hot  asphalt  cement  in  the  proportions  by 
weight  of  one  part  of  melted  asphalt  to  nine  parts  of  sand,  and 
press  into  a  briquette,  such  as  is  used  for  testing  hydraulic  cement 
or  other  convenient  mould.     Immerse  the  asphalt-coated  glass 
and  the  briquette  in  water  at  a  temperature  of  70  degrees  to  90 
degrees  Fahrenheit,  so  that  a  part  of  the  asphalt  is  below  and 
part  above  the  water.    Daily  renew  water  lost  by  evaporation.    If 
under  either  of  these  tests  the  asphalt  near  or  below  the  surface 


QO  ASPHALTS.  [CHAP.  xm. 

of  the  water  turns  a  brownish  color  and  has  a  disintegrated  ap- 
pearance, or  an  odor  of  decay,  it  will  be  rejected. 

Trinidad  Lake  Asphalt  will  clearly  show  deterioration  by 
this  test  within  a  week,  and  other  inferior  asphalts  in  a  somewhat 
longer  time. 

Binder  Course. — On  the  concrete  foundation  prepared  and 
laid  as  above  shall  be  laid  a  binder  course,  which,  after  compres- 
sion with  a  steam  roller,  shall  have  a  thickness  of  one  (i)  inch. 
The  binder  course  shall  be  made  of  crushed  stone  or  gravel,  all 
of  which  shall  be  of  such  size  as  will  pass  a  screen  having  one  (i) 
inch  openings,  which,  after  heating  to  about  250  degrees  Fahren- 
heit, shall  be  mixed  with  "ACME"  asphalt  paving  cement  in  such 
proportions  as  will  thoroughly  coat  every  particle  of  stone. 

Wearing  Surface. — The  wearing  surface  shall  be  composed 
of  — 

"Acme"   asphalt  cement   (pure  bitumen)   from..   9  to  n  per  cent. 

Sand    88  to  79  per  cent. 

Pulverized  carbonate  of  lime 3  to  10  per  cent. 

In  order  to  make  the  pavement  homogeneous,  the  propor- 
tion of  asphaltic  cement  must  be  varied  according  to  quality  and 
character  of  the  sand.  The  carbonate  of  lime  may  be  reduced  or 
omitted  entirely  when  suitable  sand  can  be  obtained.  The  sand 
and  asphaltic  cement  will  be  heated  separately  to  about  300  de- 
grees Fahrenheit.  The  pulverized  carbonate  of  lime  shall  be 
mixed  with  the  hot  sand  in  the  required  proportions,  and  then 
mixed  with  the  hot  sand  in  the  required  proportions,  and  then 
mixed  with  the  asphaltic  cement  at  the  required  temperature,  and 
in  the  proper  proportions,  in  a  suitable  apparatus,  which  will  ef- 
fect a  thorough  mixture.  The  pavement  mixture,  prepared  in  the 
manner  thus  indicated,  will  be  laid  on  the  binder  in  one  coat;  it 
will  be  brought  to  the  ground  in  carts  or  wagons,  at  a  tempera- 
ture of  about  250  degrees  Fahrenheit;  it  will  then  be  carefully 
spread  by  means  of  hot  iron  rakes  on  the  binder,  in  such  manner 
as  to  give  a  uniform  and  regular  grade,  and  to  such  depth  that, 
after  having  received  its  ultimate  compression,  it  will  have  a  thick- 
ness of  one  and  one-half  (i^)  inches  or  two  (2)  inches,  as  the 
traffic  conditions  may  demand  and  as  the  engineer  may  specify. 
The  surface  will  then  be  slightly  compressed  by  light  hand  or 


ASPHALTS    IN    1908.  9! 

steam  roller,  after  which  a  small  amount  of  hydraulic  cement  will 
be  swept  over  it,  and  it  will  then  be  thoroughly  compressed  by  a 
steam  roller  of  at  least  five  (5)  tons'  weight,  the  rolling  being  con- 
tinued as  long  as  it  makes  an  impression  on  the  surface. 

During  the  past  three  years  the  city  of  Winnipeg  has  pur- 
chased Acme  asphalt  and  has  laid  37,000  square  yards  on  its  lead- 
ing thoroughfares. 

This  city,  under  the  direction  of  Mayors  Andrews  and  Arbuth- 
not  and  City  Engineer  Col.  H.  N.  Ruttan,  bears  the  important 
distinction  of  being  the  first  municipality  to  organize  and  success- 
fully carry  out  the  laying  of  asphalt  pavements  by  the  direct  pur- 
chase of  all  the  materials  and  employment  of  labor  without  the 
intervention  of  paving  contractors.  The  results  which  have  been 
published  show  that  this  has  been  a  very  great  success  both  in 
character  and  economy  of  construction.  It  is  very  evident  that 
the  city  has  done  the  work  in  the  most  economical  manner  and 
that  it  has  saved  not  only  the  contractor's  profit,  but  the  cost  of 
bonds  and  other  expenses  of  organization,  etc.,  to  which  a  con- 
tractor is  subjected  and  which  add  very  materially  to  the  con- 
tractor's cost. 

The  city  purchased  a  complete  asphalt  paving  plant.  The 
work  was  done  under  the  general  supervision  of  Colonel  Ruttan, 
City  Engineer.  The  asphalt  construction  of  the  work  has  been 
done  during  the  past  three  years  under  the  immediate  efficient 
supervision  and  expert  advice  of  Mr.  F.  E.  Puffer,  of  Newark, 
New  Jersey,  and  formerly  Superintendent  of  the  Warren-Scharf 
Asphalt  Paving  Company. 


CHAPTER  XIV. 
ASPHALT  IN  BUILDING  CONSTRUCTION.* 

A  SPHALT  is  a  material  that  has  received  but  little  considera- 
/"\  tion  at  the  hands  of  engineers  and  architects.  When  even 
in  Paris,  the  city  of  asphalt,  the  paper  announced  during  the  siege 
of  that  city  that  "If  the  besieged  lacked  bread,  they  were,  at  least, 
not  likely  to  lack  combustibles,  for  they  could  burn  the  asphalt 
w)hich  was  in  their  streets,"  it 'is  not  surprising  that  elsewhere  the 
information  as  to  the  properties  of  th  ematerial  should  be  of  a 
meagre  character.  Lately  asphalt  has  been  more  fully  discussed 
in  its  relation  to  street  pavements.  In  this  direction  I  will  not 
trespass  upon  your  time  this  evening,  but  will  confine  myself  to 
its  use  in  the  construction  of  buildings.  Asphaltos  is  an  ancient 
Greek  word  which  passed  into  the  Latin  as  asphaltum.  The  Eng- 
lish word  asphalt  is  applied  to  the  bituminous  limestones  or  the 
bituminous  pitch  which  are  commonly  known  as  "natural  as- 
phalts." From  the  earliest  days  we  hear  of  asphalt,  and  in  the 
book  of  Genesis  we  read  of  its  use  both  in  the  Tower  of  Babel 
and  in  the  construction  of  the  ark.  It  is  said  that  th  ewalls  of 
Babylon  were  cemented  with  asphalt,  and  evidences  still  exist  of 
its  use  by  the  Egyptians.  The  first  treatise  on  asphalt  aws  pub- 
lished in  1721,  having  been  written  by  Eyrini  d'Eyrinis,  "Professor 
of  Greek,  Doctor  of  Medicine,"  and  treated  in  a  half  serious,  half 
humorous  manner  of  its  uses  for  building  purposes,  claiming  it 
as  a  panacea  for  almost  every  sickness.  This  curious  pamphlet 
was  reproduced  in  one  of  the  publications  of  Mr.  Leon  Malo, 
C.  E.,  of  Paris,  whose  works  on  asphalt  pavements  are  the  most 
practical  and  scientific  of  any  written  on  the  subject.  While  the 
claims  of  the  eccentric  doctor  that  its  use  would  stop  the  gout, 
cure  children's  chilblains,  etc.,  appear  ridiculous,  the  sanitary  ben- 
efits of  the  introduction  of  the  material  are  undoubted,  and  the 
good  effects  of  inhaling  the  smoke  of  the  hot  material  is  evi- 

*Paper   read   before   the   Architectural    Students'    Leagrue   of   Brooklyn 
May  14th,  1890,  by  Mr.  T.  H.  Boorman,  of  New  York. 


WEST    STREET   BUILDING,   NEW  YORK. 
Waterproofing  done  by  The  Sicilian  Asphalt  Paving  Company. 


"ASPHALTS' 


ASPHALTS    IN    BUILDING    CONSTRUCTION.  93 

denced  by  the  rugged  health  of  the  men  who  are  engaged  in  lay- 
ing it,  and  I  may  also  mention  that  at  the  time  the  yellow  fever 
raged  in  Memphis  a  few  years  since,  it  was  proposed  to  burn  as- 
phalt in  the  streets  to  prevent  contagion  and  kill  the  fever  germs. 
In  1834  M.  de  Puvis,  in  the  "Annales  des  Mines,"  gave  particulars 
of  the  manufacture  of  asphalt  mastic  at  Pyrimont,  and  recorded 
the  confidence  already  felt  in  that  mastic  used  for  footpaths  at 
Lyons.  The  first  asphalt  work  that  I  know  of  being  laid  in  this 
country  was  about  the  year  1838,  on  the  floors  of  the  portico  of 
the  old  Philadelphia  Merchants'  Exchange. 

Twenty-five  or  thirty  years  ago  the  European  asphalts  were 
extensively  imported,  at  a  great  expense  by  our  Government  for 
use  on  fortifications  in  covering  the  arches  over  casemates,  maga- 
zines, vaults  and  for  other  similar  purposes.  Since  1872  they  have 
been  imported  by  asphalt  companies  and  used  in  buildings  of  all 
descriptions. 

Rock  asphalt  is  a  lime  ore  impregnated  naturally  by  a  geo- 
logical phenomenon,  still  but  imperfectly  explanied,  with  bitumen 
in  the  proportion  of  8  to  17  for  100.  It  is  found  in  strata  like  coal. 
The  principal  mines  are  the  Limmer,  near  Hanover,  Germany,  the 
Neuchatel  in  Switzerland,  and  the  Seyssel  in  France.  For  street 
work,  the  mines  at  Ragusa,  Sicily,  produce  a  rock,  rich  in  bitu- 
men, which  has  been  used  in  New  York  and  other  American  cities 
with  great  success.  On  the  coast  of  California,  near  Santa  Bar- 
bara, and  also  in  certain  portions  of  Kentucky,  Colorado,  Utah 
and  New  Mexico,  are  found  large  beds  of  sandstone  containing 
from  15  per  cent,  to  20  per  cent,  of  bitumen.  Recently  this  ma- 
terial has  been  used  for  paving  in  cities  on  the  Pacific  coast. 

For  use  in  buildings  the  natural  rock  is  manufactured  into 
what  is  known  as  asphalt  mastic  in  the  following  manner: 

The  rock,  after  being  reduced  to  powder,  is  placed  in  cylin- 
drical kettles,  in  which  about  8  per  cent,  of  Trinidad  asphalt  has 
previously  been  placed  and  melted.  The  mass  is  stirred  by  re- 
volving arms  and  agitators,  at  a  temperature  of  about  350°  F., 
for  about  five  hours.  It  is  thus  thoroughly  "cooked,"  and  is  then 
run  out  of  the  kettles  into  moulds,  where  it  cools  in  the  form  of 
cakes  or  blocks,  weighing  from  50  to  60  pounds  each.  These  are 
stamped  wit  hthe  brands  of  th  emines  and  imported  into  this 
country.  The  mastic  so  prepared  shows  an  analysis,  according 
to  a  report  on  Limmer  blocks,  manufactured  by  "The  United 


94  ASPHALTS.  [CHAP.  xiv. 

Limmer  &  Vorwohle  Rock  Asphalt  Co.,  Ltd.,"  prepared  for  the 
Department  of  Public  Works,  Philadelphia,  by  Dr.  Charles  M. 
Cresson,  as  follows : 

Bitumen    , 14.30  per  cent. 

Carbonate  of  lime 85.20       " 

Silica,  alumina  and  oxide  of  iron 50        " 

100.00       " 

To  use  it  for  walks  or  floors  the  material  is  again  heated  in 
suitable  kettles  in  the  following  proportions : 

Mastic  blocks   (broken) 60  Ibs. 

Trinidad  asphalt   4    " 

Fine  gravel  and  sand 36    " 


100    ' 

This  is  "cooked"  for  about  five  hours  at  a  temperature  of 
about  400°  F.,  great  care  being  taken  constantly  to  stir  the  mix- 
ture. It  is  then  taken  out  of  the  kettle  by  th  ebucketful  and 
poured  on  the  foundation  prepared,  its  consistency  being  such 
that  it  will  flow  very  slowly.  It  is  then  spread  by  means  of  wooden 
trowels,  and  compressed  and  smoothed  by  rubbing,  as  in  plas- 
tering. 

Sidewalks  so  laid  on  concrete  foundations  have  given  great 
satisfaction  in  Paris,  and  are  almost  exclusively  used  throughout 
that  city.  Their  superficial  area  is  nearly  5,000,000  square  yards, 
and  their  length  probably  exceeds  1,000  miles. 

In  London,  Berlin  and  Hanover,  also,  sidewalks  of  this  ma- 
terial are  used  very  extensively — in  the  latter  city  almost  entirely. 

Having  thus  briefly  described  the  preparation  of  asphalt 
mastic,  I  will  now  speak  of  its  uses.  From  the  cellar  to  the  roof, 
asphalt  has  been  used  where  the  requirements  have  been  water 
and  fireproof  floors.  Its  principal  merits  are  its  utter  impervious- 
ness  to  water  or  damp,  and  its  elasticity,  whereby  cracking,  espe- 
cially from  the  influence  of  frost,  is  prevented.  Also  from  a  sani- 
tary point  of  view  the  advantages  of  asphalt  are  incontestable,  for 
it  possesses  great  antiseptic  properties,  and  owing  to  its  having 
no  joints  it  is  impossible  for  particle  of  animal  or  vegetable  matter 
to  lodge  in  crevices  and  putrefy.  It  greatly  promotes  cleanliness, 
as  it  can  be  easily  washed,  and  for  this  reason  is  invaluable  in  hos- 
pitals, breweries,  stables,  etc. 


ASPHALTS    IN    BUILDING    CONSTRUCTION.  95 

Asphalt  first  appears  in  your  specifications  as  under  the  item 
of  "Damp  Course."  It  is  advisable  to  lay  throughout  the  walls 
on  the  grade  of  the  cellar  floor  half  an  inch  of  asphalt,  with  a  lap 
of  about  two  inches  on  the  inside,  so  allowing  a  connection  with 
the  asphalt  finish  of  the  cellar  floor  and  hermetically  sealing  the 
house  from  damp,  noxious  gases  and  vermin.* 

In  residences  you  will  probably  consider  you  have  done  your 
duty  by  asphalt  if  you  have  thus  specified  for  your  damp  course 
and  cellar  floor,  in  the  latter  by  the  way,  three-fourths  of  an  inch 
of  asphalt  on  three  inches  of  hydraulic  cement  concrete  will  serve 
the  desired  purpose  of  a  durable  damp-proof  floor. 

The  yards  of  city  residences  are  now  frequently  laid  with 
asphalt,  the  material  being  peculiarly  adapted  to  the  roller-skates 
and  tricycles  of  the  younger  members  of  a  family. 

From  a  building  then,  in  which  only  one  floor,  the  cellar,  is 
required  to  be  of  asphalt,  let  us  consider  where  every  floor  and 
the  roof  can  be  of  this  material ;  in  printing  houses,  lithographing 
establishments,  breweries,  sugar  refineries  and  slaughter  houses, 
you  will  often  find  this  material  used  throughout.  This  year, 
however,  sees  a  novelty  in  construction  with  asphalt.  Theophilus 
P.  Chandler,  Jr.,  architect,  of  Philadelphia,  is  using  rock  asphalt 
on  every  floor  of  a  large  apartment  house ;  the  carpets  will  lay  on 
the  asphalt  being  fastened  down  to  narrow  strips  of  wood  set 
against  the  partitions  when  the  asphalt  is  laid.  Now,  I  fancy  I 
hear  you  say,  "Well,  asphalt  is  not  pleasant  in  appearance."  Why, 
gentlemen,  the  Mayor's  private  office  in  the  great  City  Buildings 
of  Philadelphia,  the  greatest  municipal  edifice  in  the  country,  is 
laid  with  asphalt  with  a  border  of  colored  tiles. 

Your  association  I  am  especially  pleased  to  address  tonight, 
for  the  reason  that  I  find  you  wish  to  listen  to  practical  papers; 
while  so  many  of  you  are  favorably  known  as  artists  with  your 
pencils,  you  still  are  disposed  to  look  thoroughly  into  the  more  pro- 
saic details  of  your  profession. 

The  "House  Beautiful"  must  also  be  the  "Home  Healthy/' 
and  while  the  people  delight  in  the  beauties  of  architecture 
evolved  from  your  pencils,  they  also  wish  to  know  that  light,  heat, 


*In  connection  with  this  use  of  asphalt  mastic  I  was  informed  recently  by 
Mr.  J.  T.  Brumshagen,  of  Baltimore,  that  in  1860  the  building  laws  of  German 
cities  at  that  time  insisted  on  a  damp-proof  course  in  every  building  and  would 
allow  of  the  use  of  nothing  but  rock  asphalt  for  that  purpose. 


96  ASPHALTS.  [CHAP.  xiv. 

ventilation  and  sanitation  have  not  been  neglected  in  your  plans. 
This  you  realize,  and  in  this  is  your  strength. 

These  remarks  are  intended  to  obtain  your  indulgence,  while 
I  venture  to  make  a  few  suggestions  as  to  methods  of  drawing 
specifications  for  asphalt  work  gleaned  during  eighteen  years  of 
study  and  prosecuting  such  work,  including  two  years'  experience 
as  asphalt  expert  for  the  Department  of  Public  Works  and  for 
the  Department  of  Public  Parks  of  New  York  city. 

For  sidewalks  and  courtyards  I  would  recommend  one  inch 
of  rock  asphalt  on  four  inches  of  Portland  cement  concrete,  made 
with  the  usual  proportions  of  cement,  stone  and  sand.  For  cellar 
floors  and  floors  not  subjected  to  much  wear  three-fourths  of  an 
inch  of  Limmer  or  other  standard  brand  of  mastic  will  suffice. 
For  floors  of  breweries,  stables,  slaughter  houses,  sugar  refineries, 
one  inch  is  requisite.  For  ordinary  hospital  floors  three-fourths 
of  an  inch  thickness  will  suffice.  For  the  roofs  of  fireproof  build- 
ings on  the  top  of  concrete  I  would  recommend  an  inch  and  a 
quarter  of  rock  asphalt,  in  two  coats,  laid  on  three  thicknesses 
of  felt  paper,  cemented  with  Trinidad  asphalt  cement  or  bitumen. 

This  bitumen  is  refined  Trinidad  asphalt  which,  after  a  treat- 
ment with  petroleum  residuum,  forms  an  asphaltic  cement  which 
can  be  used  with  good  effect  for  the  coating  of  walls  where  they 
come  in  contact  with  the  earth.  I  have  seen  specifications  for 
the  coating  of  walls  with  rock  asphalt,  but  the  weight '  of  that 
material  is  a  drawback  to  its  application  vertically,  and  for  this 
purpose  and  for  covering  vaults  and  arches  the  Trinidad  asphalt 
can  be  advantageously  used.  In  cases  where  expense  is  no  ob- 
ject I  would  say  that  the  rock  asphalt  can  be  used  vertically,  but 
the  work  is  expensive  and  tedious.  I  must  not  omit  to  call  your 
attention  to  asphaltic  masonry  for  engine  beds. 

Of  the  use  of  asphalt  in  foundations,  two  very  interesting 
examples  are  given  by  W.  H.  Delano,  in  a  paper  read  before  the 
English  Institute  of  Civil  Engineers  in  1880.  One  was  the  foun- 
dation of  a  rock-disintegrator,  running  at  a  high  rate  of  speed.  It 
was  first  built  upon  a  foundation  of  ordinary  concrete.  On  the 
opposite  side  of  the  street  was  an  establishment  for  painting  on 
glass  and  china,  where  fine  grades  of  work  were  required.  The 
vibrations  from  the  disintegrator  wtere  so  great  that  the  business 
of  the  glass  painter  was  rendered  impossible.  He  threatened  suit 
for  heavy  damages,  whereupon  the  foundations  of  the  disinte- 


w 

O  2 

3  P 

I* 

p    H 


"A  S  P  HALTS' 


ASPHALTS    IN    BUILDING    CONSTRUCTION.  97 

grator  were  removed  and  rebuilt  in  asphalt  concrete.  The  result 
was  entirely  successful,  the  vibrations  becoming  imperceptible. 
The  second  case  was  the  foundation  of  a  large  trip-hammer, 
weighing  forty-five  tons,  which  was  erected  at  the  Paris  Exposi- 
tion of  1867.  I*1  order  to  reduce  the  concussion,  this  was  built 
in  asphalt  concrete,  and  with  entire  success.  At  the  close  of  the 
Exposition,  the  concrete  was  so  tough  that  it  was  found  impos- 
sible to  make  an  impression  on  it  with  a  pick  or  chisel.  As  blast- 
ing was  not  permitted,  the  foundation  had  to  be  left  in  position, 
and  it  may  be  still  there. 

In  these  cases  the  concrete  was  made  from  rock  asphalt 
mastic.  The  proportions  were  60  per  cent,  of  broken  stone  and 
40  of  gritted  asphalt  mastic.  It  was  tamped  between  wooden 
frames,  secured  by  iron  cross-bolts,  and  these  bolts  were  left  in 
the  material. 

In  closing  I  would  impress  on  you  that  the  use  of  asphalt 
has  been  militated  against  not  only  by  the  lack  of  general  knowl- 
edge of  the  material  but  by  the  failure  of  coal  tar  products  which, 
under  the  name  of  "asphaltic  cement,"  have  led  the  public  to  con- 
demn the  legitimate  article.  As  you  do  not  expect  to  find  the 
golden  balls  of  the  pawnbroker  to  be  gold,  neither  must  you 
expect  to  have  natural  rock  asphalt  used  in  your  buildings  if  you 
specify  for  "asphaltic  cement." 


CHAPTER  XV. 
DUSTLESS  ROADS. 

WHEN  in  England  in  1904  the  writer  became  interested  in 
the  laying  of  dust  on  macadam  roads,  and  found  in  New- 
ark, Nottingham,  the  application  of  "Westrumite." 

This  is  a  patented  chemical  preparation  used  in  the  making 
of  roads  and  for  laying  the  dust  in  roads,  streets  and  open  spaces, 
and  is  composed  of  oily  substances  rendered  oluble  in  water  by 
certain  patented  chemical  and  mechanical  processes. 

Until  the  advent  of  "Westrumite"  there  were  said  to  be  only 
three  agents  which  could  la  yany  claim  to  consideration  as  pos- 
sible dust-layers,  although  none  of  them  offered  a  true  solution  of 
the  dust  problem.  These  w^ere  water,  tar  and  crude  oil. 

Since  then  the  author  has  investigated  other  temporary  ap- 
plications, for  relief  from  the  disastrous  effects  of  dust  which, 
since  the  advent  of  the  automobile,  as  a  regular  conveyance  and 
not  a  luxury,  has  proved  a  menace  to  the  health  as  well  as  the 
comfort  of  the  residents  and  pedestrians  on  our  macadam  roads. 

There  are  many  temporary  allayments  which  might  be  men- 
tioned, but  in  all  of  which  asphalt  or  liquid  asphalt  have  little  or 
no  part,  and  so  they  are  not  considered  in  this  book. 

In  the  year  book  of  the  Department  of  Agriculture  for  1902, 
Col.  James  W.  Abbott,  then  special  agent,  Rocky  Mountain  and 
Pacific  Coast  Division,  Office  of  Public  Road  Inquiries,  wrote 
that  public  attention  was  first  called  to  the  utility  of  crude  petro- 
leum oil  in  road  betterment  through  experiments  made  by  the 
county  of  Los  Angeles  in  California  in  1898,  where  six  miles  of 
road  were  oiled  in  that  year  under  the  direction  of  the  super- 
visors. The  sole  purpose  of  this  work  was  to  lay  the  dust,  which, 
churned  beneath  the  wheels  of  yearly  increasing  travel  during  the 


DUSTLESS    ROADS.  99 

long  dry  seasons  in  that  region,  had  become  a  most  serious  nui- 
sance. 

The  following  year  this  mileage  was  a  little  more  than  dou- 
bled in  that  county,  and  other  counties  in  California  also  began 
experiments  along  the  same  line. 

From  the  very  first  the  results  obtained  were  so  astonish- 
ingly successful  that  the  practice  rapidly  increased.  It  spread 
through  every  county  in  Southern  California,  and  then  began  to 
work  north.  Since  then  it  has  extended  from  near  the  Mexican 
line,  on  the  south,  to  Durham,  in  Butte  County,  on  the  north,  a 
stretch  covering  sections  of  quite  widely  differing  climatic  condi- 
tions, with  an  aggregate  of  about  750  miles  of  county  roads  and 
city  streets  oiled  for  one  or  more  years.  Oil  has  been  used  on  the 
principal  driveways  of  Golden  Gate  Park,  San  Francisco.  The 
mountain  stage  road  into  the  Yosemite  National  Park  has  been 
oiled  for  a  distance  of  30  miles,  from  its  initial  terminus  at  Ray- 
mond to  eight  miles  above  Wawona.  In  California  it  has  long 
passed  the  experimental  stage. 

In  the  California  asphalts  the  asphaltene  and  petrolene  are 
found  combined  in  very  variable  proportions.  In  the  petroleums 
which  contain  them  the  combinations  of  all  the  hydrocarbons 
differ,  not  only  in  the  same  immediate  oil  field,  but  in  the  separate 
strata  and  even  in  the  same  stratum. 

The  very  heaviest  of  the  oils  have  almost  the  specific  gravity 
of  water,  while  a  naphtha  may  be  75°  B.,  or  even  lighter. 

From  the  very  beginning  of  the  use  of  crude  oil  for  roads  in-. 
California  it  seems  to  have  been  understood  that  it  was  the  as- 
phalt in  the  oil  which  acted  as  the  binder,  and  consequently  they 
have  always  sought  very  heavy  oils  for  that  purpose.  It  might 
naturally  be  supposed  that  the  heavier  the  oil  the  greater  the 
percentage  of  asphalt.  While  this  is  approximately  true,  it  does, 
not  necessarily  follow.  A  crude  oil  is  a  complex  mixture  of  light 
and  heavy  hydrocarbons,  and  its  resultant  gravity  depends  upon 
the  amount  of  each  kind  which  it  contains. 

Table  VII.  on  the  next  page  was  compiled  from  the  notes  of 
eleven  analyses  of  crude  oils  made  in  California  by  D.  B.  W.  Alex- 
ander, now  the  Denver  chemist  of  the  Colorado  Paving  Company. 
The  original  determinations  covered  many  other  data,  but  in  the 
table  only  the  degrees  Baume  and  the  percentage  of  asphalt  are 
shown : 


ioo  ASPHALTS.  [CHAP.  xv. 

All  of  these  oils  doubtless  contained  a  small  amount  of  min- 
eral matter  which  affected  the  specific  gravity  and  disturbed  the 
relation  between  it  and  the  asphalt  contained. 

TABLE  VII. 

ANALYSES  OF  CRUDE  OILS. 

Per  cent.  Per  cent. 

~B.           asphalt.  °B.  asphalt. 

10.4              64.1  15.7  39.9 

12.2              45  19  28 

13                  61  19.3  32.8 

!375             59  23  25.4 

I54              32.1  23  43 
I                    J5-5              50.2 

The  above  table  shows  that  in  selecting  a  petroleum  for  road 
purposes  the  specific  gravity  alone  is  not  a  sure  guide.  It  also 
shows  that  the  California  practice  of  selecting  a  noil  of  12°  B.  to 
14°  B.  can  be  depended  upon  for  good  results. 

Mr.  L.  B.  De  Camp,  of  San  Francisco,  suggests  the  follow- 
ing as  a  crude  test  used  by  him ;  it  is  probably  closer  than  the 
Baume  measurement: 

Pour  a  definite  amount  of  crude  petroleum  into  a  graduated 
glass  and  add  an  equal  amount  of  refined  petroleum.  Stir  thor- 
oughly together  and  add  to  the  mixture  2  per  cent,  of  commercial 
sulphuric  acid.  Again  stir  sthoroughly  and  the  asphalt  will  pre- 
cipitate to  the  bottom.  The  percentage  which  it  represents  of  the 
original  amount  of  oil  can  be  measured  by  the  graduations  on  the 
glass. 

In  California,  where  the  aim  is  to  always  use  an  oil  contain- 
ing as  much  asphalt  as  possible,  the  amount  of  oil  required  for  a 
1 6- foot  roadway  varies  between  250  and  400  barrels  of  42  gallons 
each  to  the  mile.  This  depends  upon  the  thickness  of  the  oil  crust 
made,  the  porosity  of  the  material,  and  the  percentage  of  asphalt  in 
the  oil. 

The  quicker  this  oil  crust  is  made  the  better.  If  two  applica- 
tions are  made  to  a  porous  material  and  the  oil  properly  stirred  in 
each  time,  the  crust  will  be  finished.  If  the  hard  material  is  a 
clay,  it  should  have  at  least  two  treatments.  One  will  be  sufficient 
for  macadam.  A  dusty  clay  will  require  some  gravel  added  for 
the  first  application.  On  the  second  application  the  crust  which 
has  begun  to  form  should  not  be  disturbed,  but  after  all  the  oil 


THE  HOTEL  KNICKERBOCKER,   NEW  YORK. 

Waterproofing  by  The  Union  Construction  &  Waterproofing  Company 
of  New  York. 


"A  S  PH  A  LT  S' 


BUSTLES^  : 'ROADS.  101 

sinks  in  that  will  a  layer  of  sand  should  be  sprinkled  on  top.  In 
this  oiled  crust  the  bottom  will  be  made  from  the  clay  dust  and 
the  top  mostly  fro  mthe  added  sand,  while  the  middle  will  be  a 
mixture  of  the  two. 

In  the  first  experiments  a  part  of  the  oil  was  generally  put 
on  the  first  year,  and  the  crust  was  completed  the  second  or  third 
year.  The  first  year  the  thin  crust  was  often  broken  through  and 
a  hole  was  left  in  the  road. 

After  the  oiled  crust  has  once  been  properly  formed  all  the 
oil  required  will  not  exceed  25  barrels  to  the  mile  for  repairs  in 
each  subsequent  year. 

During  the  spring  and  summer  of  1905  the  Office  of  Public 
Roads  cooperated  with  Mr.  Sam  C.  Lancaster,  city  engineer  of 
Jackson,  Tenn.,  and  chief  engineer  of  the  Madison  County  Good 
Roads  Commission,  in  making  a  series  of  careful  experiments  at. 
Jackson,  Tenn.  Tests  were  made  of  the  utility  of  crude  Texas 
oil  and  several  grades  of  its  residue  when  applied  to  earth  and 
macadam  roads. 

Seven  tank  cars  of  oil,  given  by  some  Texas  and  Louisiana 
companies,  were  used  at  Jackson.  It  varied  in  quality  from  a 
light,  crude  oil  to  a  heavy,  viscous  residue  from  the  refineries. 
Over  seven  miles  of  country  road  and  several  city  streets  were 
treated. 

At  first,  some  of  the  lighter  crude  oils  were  applied  with  the 
same  tank  wagon  that  was  used  for  the  tar.  Hose  and  brooms 
were  used  to  spread  the  oil,  and  practically  the  same  process  was 
followed  as  with  the  tar.  The  oil  soaked  into  the  macadam  very 
quickly  and  left  on  coating  on  top.  It  caused  the  light  covering 
of  sand  which  was  applied  to  pack  down  and  gave  the  road  a  dark 
color. 

It  was  soon  noticed  that  the  preliminary  sweeping  was  un- 
necessary, as  the  roads  were  practically  free  from  dust  and  oil 
would  penetrate  the  surface.  The  removal  of  detritus  was  a  loss 
to  the  road,  which  had  to  be  replaced  by  sand  to  prevent  excessive 
wear  on  the  stone.  It  was  later  found  that  it  was  much  cheaper 
to  use  an  ordinary  street  sprinkler  than  the  tank  wagon,  and  in 
this  case  spreading  the  oil  with  brooms  was  unnecessary. 

The  crude  oil  was  used  cold,  and  the  cost  of  applying  it  by 
the  different  methods  used  is  given  below. 

On  a  city  street  8,266  square  yards  were  treated  at  the  rate 


102  "£$PfrALTS.  [CHAP.  xv. 

of  0.48  of  a  gallon  of  oil  per  square  yard  with  the  use  of  the  tank 
wagon  and  hose.  The  cost  of  labor  per  square  yards  was  as 
follows : 

Sweeping  street  $0.001 1 

Filling  tank  and  hauling 0008 

Oiling  street    0024 

Spreading  sand 0014 


Total    OO57 

On  a  country  road  2,000  gallons  were  spread,  'covering  5,206 
square  yards,  at  a  rate  of  0.38  of  a  gallon  per  square  yard.  The 
average  haul  was  one  mile.  Only  the  manure  was  removed  be- 
fore oiling.  The  cost  of  labor  averaged  $0.0033  Per  square  yard. 

It  took  nine  men  thirty  minutes  to  spread  500  gallons,  or  one 
tank  load,  and  the  1 8-foot  road  was  covered  at  the  rate  of  1,860 
feet  per  hour.  It  took  twenty-eight  minutes  to  fill  the  tank  car 
with  oil.  With  an  ordinary  street  sprinkler,  one  man  and  team 
spread  one  load  of  600  gallons  of  oil  in  fifteen  minutes.  The 
sprinkler  thus  spread  600  gallons  in  one-half  the  time  that  it  took 
nine  men,  with  the  tank  wagon,  to  spread  500  gallons. 

The  heavy  residual  oils  were  so  thick  when  cold  that  they 
would  not  run  through  a  2-inch  fire  hose  attached  to  the  rear  of 
the  tank  wagon,  and  it  was  necessary  to  pump  the  oil  upon  the 
road.  The  pump  with  which  the  tank  was  charged  was  used  for 
this  operation.  Only  one  tank  wagon  (500  gallons)  of  the  heavy 
oil  was  applied  cold.  It  formed  a  thick,  sticky  mass  on  the  top  of 
the  road  that  rolled  about  under  pressure  and  seemed  to  have  an 
unlimited  capacity  for  absorbing  the  sand  which  was  spread  upon 
it.  The  street  had  to  be  cleared  of  the  greater  part  of  this  mass 
of  oil  and  sand  within  a  short  time. 

After  this  experience  the  oil  was  heated  in  the  car  by  steam, 
and  better  results  followed.  It  still  ran  slowly  through  the  hose 
and  nozzle,  and  it  was  found  cheaper  to  take  off  the  hose  and 
allow  the  oil  to  flow  from  the  outlet  of  the  tank  directly  upon  the 
road,  where  the  men  swept  it  over  the  surface  with  brooms.  An 
air  pump  was  tried,  to  increase  the  floflw  of  the  tank  by  pressure, 
but  the  tank  was  not  tight  enough  to  prevent  the  escape  of  air, 
and  this  experiment  was  unsuccessful. 

Twenty-four  hours  after  the  application  of  the  residual  oil  it 


DUSTLESS    ROADS.  103 

was  covered  with  sand  or  limestone  screenings,  and  in  four  days  it 
was  firm  enough  to  bear  traffic  without  showing  any  wheel  tracks. 
It  shed  the  water  well  in  a  violent  rain  storm. 

The  following  was  the  cost  per  square  yard  of  putting  re- 
sidual oil  on  city  streets  with  the  use  of  the  tank  wagon.  Ap- 
proximately 0.71  of  a  gallon  of  oil  was  used  per  square  yard. 

Sweeping  street   $0.0010 

Heating,  loading  and  hauling 0017 

Oiling  street 0029 

Spreading  sand    0022 


Total    0078 

Excellent  results  can  be  secured  by  the  use  of  this  heavy 
residual  oil  if  it  can  be  applied  to  the  surface  of  the  road  at  a 
temperature  approaching  the  boiling  point. 

The  medium  grade  of  oil,  which  was  tried  next,  is  classed  by 
the  refiners  as  "steamer  oil."  It  wa  sheavy  enough  to  leave  a 
slight  coating  on  the  surface,  which  made  a  very  compact  cover- 
ing with  the  dust  of  the  road.  Only  the  heavy  matter  was  re- 
moved from  the  surface  of  the  road  before  applying  the  oil.  It 
was  heated  by  steam  in  the  car,  but  was  not  hot  when  it  reached 
the  road.  It  was  not  safe  to  build  a  fire  in  the  tank  wagon,  and 
the  best  road  surface  was  obtained  where  the  oil  was  at  the  high- 
est temperature.  Some  method  of  heating  the  oil  safely  on  the 
road  would  greatly  improve  the  results.  This  could  be  accom- 
plished with  a  steam  straction  engine  having  steam  coils  con- 
nected with  the  tank,  the  engine  hauling  and  heating  the  tank 
while  spreading  the  oil.  Most  of  this  oil  was  applied  with  the 
street  sprinkler,  and  it  sprayed  readily  when  hot. 

In  applying  the  greater  part  of  the  oil  on  the  country  roads 
the  following  men  and  equipment  were  used:  A  foreman  at  $2 
per  day;  6  laborers  at  $1.25  per  day  for  working  on  the  road  and 
pumping  oil  at  the  car ;  I  tank  wagon  and  I  street  sprinkler  at  $3 
each  per  day;  2  firemen  at  $1.50  per  day,  and  I  ton  of  coal.  This 
force  spread  in  one  day  3  tank  wagons  of  1,500  gallons  and  3 
sprinkler  tank  loads  of  1,800  gallons,  making  a  total  of  3,300 
gallons. 

No  sweeping  was  done  on  the  country  roads  except  to  re- 
move manure  and  to  spread  the  oil  where  it  was  inclined  to 


104  ASPHALTS.  [CHAP.  xv. 

puddle.  No  sand  or  other  material  was  applied  to  the  road  after 
oiling. 

More  than  seven  months  have  now  elapsed  since  the  work 
was  done.  The  light  crude  oil  has  produced  little  if  any  perma- 
nent results.  Te  roads  where  it  was  applied  are  but  slightly 
changed,  and  some  dust  arises  on  them  from  traffic.  The  only 
apparent  result  is  a  slightly  darker  collore  on  the  "shoulders"  of 
the  road,  and  but  little  difference  can  be  noticed  between  this  and 
other  sections  of  the  road  which  were  not  treated.  This  oil  was 
too  volatile  for  the  purpose,  and  where  it  has  to  be  shipped  for 
any  distance  does  not  justify  the  expense  of  using  it. 

The  medium  "steamer  oil"  fro  mTexas  has  given  good  re- 
sults. There  is  a  thin  surface  coat  of  dust  packed  down  that  pro- 
tects the  stone  from  the  grind  -  and  pounding  of  traffic.  This 
effect  is  very  noticeable  in  driving  over  it.  The  harsh  grinding 
noise  of  the  wheels,  which  is  pronounced  on  the  novaculite  sur- 
face, disappears  at  once,  and  there  is  decided  relief  in  driving 
'upon  it.  It  is  practically  noiseless.  This  coating  is  perhaps  one- 
eighth  of  an  inch  thick,  and  is  not  a  concrete,  but  compacted 
dust,  which  is  made  to  cohere  by  the  oil  with  which  it  is  saturated. 
This  road  does  not  wash  or  "pick  up,"  and  the  wear  on  the  rock 
is  much  decreased. 

A  good  macadam  road  forms  a  wearing  coat  of  fine  material, 
which  is  ncessary  to  its  existence.  If  this  coat  is  removed,  an- 
other is  formed  and  the  life  of  the  road  is  gauged  by  the  rapidity 
with  which  the  detritus  is  removed  from  the  surface.  The  more 
rapidly  it  is  removed  the  shorter  will  be  the  life  of  the  road.  The 
important  result  of  applying  the  "steamer  oil"  was  that  the  wear- 
ing cost  was  fixed  and  held  to  the  surface,  consequently  the  life 
of  the  road  will  be  much  greater.  Of  course  some  of  it  has  blown 
and  washed  away,  but  it  is  perhaps  safe  to  say  that  the  loss  is 
decreased  by  at  least  75  per  cent. 

The  best  results  were  obtained  with  the  heavier  oils  when 
the  oil  was  hot.  The  road  treated  with  the  heaviest  oil  is  entirely 
dustless.  Teams  passing  from  the  bare  macadam  upon  the  oiled 
road  show  this,  for  the  cloud  of  dust  behind  a  wagon  dissapears  at 
once,  and  the  oiled  roads  can  be  cleaned  or  swept  as  well  as  the 
tarred  roads.  There  is  but  little  noise  even  from  the  horses' 
hoofs. 

Another  experiment  was  tried  of  treating  an  ordinary  earth 


•A  S  P  H  A  L  T  S' 


DUSTLESS    ROADS.  105 

road  with  the  heavy  oil  after  it  had  been  shaped  and  graded.  The 
soil  was  composed  largely  of  sand  and  the  oil  was  harrowed  into 
it  and  the  road  rolled.  This  piece  of  road  has  become  fairly 
smooth  and  arm  enough  to  bear  traffic.  It  is  not  hard  like  mac- 
adam and  has  small  wheel  marks.  It  is  about  as  good  as  the  usual 
earth  road  where  the  soil  packs  well  in  fair  weather.  It  is  an  im- 
provement on  the  old  road,  as  the  sandy  soil  was  cut  into  ruts, 
but  it  can  hardly  be  recommended  for  use  where  the  oil  has  to 
be  shipped  a  great  distance  and  is  high  in  price. 

The  experiments  outlined  above  were  in  the  main  successful. 

Another  series  of  experiments  was  conducted  in  1907  by  the 
Office  of  Public  Roads  at  Bowling  Green,  Ky.  The  materials 
used  were  Kentucky  rock  asphalt  tested  for  its  fitness  as  a  binder 
in  macadam  construction,  crude  Kentucky  oil,  and  a  special  prep- 
aration of  residuum  oils,  the  last  two  of  which  were  used  as  dust 
preventives.  This  work  was  done  in  cooperation  with  the  au- 
thorities of  Warren  County  and  lay  just  beyond  the  city  limits 
of  Bowling  Green.  The  location  of  each  section  of  experimental 
work  is  given  in  connection  with  its  description. 

The  rock  asphalt  used  in  this  experiment  is  a  natural  product 
formed  in  the  Chester  group  of  subcarboniferous  rocks  over  a 
course  extending  through  Breckinridge,  Grayson,  Edmonson, 
Logan,  and  Warren  counties  in  Kentucky,  marking  the  edge  of 
the  coal  fields  lying  in  the  wesetrn  part  of  that  State.  It  is  fine- 
grained sandstone  which  in  the  past  has  been  impregnated  with 
mineral  pitch  or  bitumen,  the  latter  averaging  from  6  to  8  per 
cent,  with  a  maximum  of  12  per  cent.  Both  appearance  and  im- 
pregnation are  irregular,  for  it  is  generally  found  in  pockets  rather 
than  in  distinct  continuous  veins,  and  the  distribution  of  the  bitu- 
men over  the  pocket  ranges  from  a  mere  trace  to  saturation. 

The  quarrying  and  first  crushing  of  rock  asphalt  are  not  un- 
like that  of  other  rock  intended  for  macadam  or  concrete  work. 
After  having  been  broken  into  pieces  to  pass  through  a  2-inch 
ring,  it  is  conducted  to  a  series  of  roll  crushers,  consisting  of 
parallel  steel  cylinders.  The  bitumen  in  the  rock  gives  sufficient 
adehsion  to  carry  the  material  through  the  rolls,  once  it  has  been 
forced  against  them.  The  finished  product  after  crushing  is  a 
mass  of  individual  grains  of  sand,  each  thoroughly  coated  with  a 
film  of  mineral  pitch  sujciently  glutinous  to  cause  it  to  adhere  to 
surrounding  grains  and  to  pack  very  firmly  if  subjected  to  pres- 


io6  ASPHALTS,  [CHAP.  xv. 

sure.  If  chilled  when  compacted,  a  lump  becomes  very  hard  and 
tough;  if  warmed  in  the  hand,  the  bitumen  becomes  soft  and  semi- 
fluid and  the  individual  grains  of  sand  fall  from  the  mass  of  their 
own  weight.  When  freshly  crushed  it  is  of  rich  dark  brown  color 
with  a  slight  lustre  which  gradually  disappears  as  the  bitumen 
hardens  and  dries. 

The  test  was  made  on  what  is  known  as  Cemetery  pike,  run- 
ning east  from  the  city  limits  of  Bowling  Green.  It  is  the  main 
thoroughfare  leading  from  the  southern  and  eastern  parts  of 
Warren  County  to  Bowling  Green,  the  county  seat,  and,  besides 
being  the  route  for  heavy  rural  traffic,  it  passes  extensive  gravel 
beds  and  timber  lands  from  which  heavy  loads  are  being  con- 
stantly taken  on  narrow  tires. 

The  form  of  construction  origianlly  adopted  was  a  2O-foot 
Telford  road.  When  this  surface  had  been  worn  away  under 
traffic  and  the  foundation  exposed  it  was  repaired  and  brought 
to  grade  with  a  sharp  gravel  containing  about  20  per  cent,  of 
sand  and  clay.  This  bed  of  gravel  was  about  8  inches  thick,  com- 
pacted. Previously  to  the  experiments  it  was  loosened  to  a  depth 
of  four  inches  by  means  of  a  spiked  roller  and  a  heavy  harrow, 
and  was  shoveled  out  by  hand.  The  subgrade  was  then  made  to 
conform  to  the  crown  of  the  roadway,  which  was  planned  to  be 
4^/2  inches  in  9  feet,  or  an  average  of  one-half  inch  per  foot.  The 
gravel  removed  in  shaping  the  subgrade  was  used  for  repairs  on 
the  roadway  beyond  the  work. 

After  thoroughly  compacting  the  subgrade  with  a  roller  the 
wearing  course  of  stone  was  laid.  It  consisted  of  limestone 
crushed  to  range  from  I  inch  to  i^  inches  in  largest  dimension 
and  was  spread  to  a  uniform  depth  of  4  inches.  This  course  was 
then  rolled  once  to  turn  down  the  sharp  edges  of  the  stone  and 
form  a  smooth,  even  surface.  No  further  attempt  was  made  to 
reduce  the  voids  in  the  stone  by  compacting  it,  as  these  were  to 
be  filled  with  the  rock  asphalt.  This  material  was  then  thrown 
on  with  shovels  from  wagons  and  dumping  boards  along  one  side 
of  the  road.  It  was  spread  to  a  depth  of  i^  inches,  care  being 
taken  to  break  all  lumps  and  to  work  all  the  asphalt  rock  possible 
into  the  interstices  of  the  stone  without  disturbing  the  latter. 

As  the  work  progressed  the  roller  was  kept  moving  back  and 
forth  parallel  to  the  axis  of  the  roadway  and  was  worked  from 
the  outer  edge  to  the  crown  as  in  ordinary  macadam  construe- 


DUSTLESS    ROADS.  107 

tion.  To  prevent  the  adhesion  of  the  bitumen  to  the  wheels  of 
the  roller  a  light  coating  of  natural  cement  was  dusted  over  the 
rock  asphalt,  but  it  was  soon  found  that  in  moving  the  roller  off 
the  work  at  the  end  of  each  rolling  enough  dust  collected  on  the 
wheels  to  prevent  adhesion  and  no  more  cement  was  used.  The 
stone  had  not  been  thoroughly  compacted  before  applying  the 
asphalt,  and  for  this  reason  a  very  perceptible  wave  in  the  surface 
preceded  the  roller,  causing  the  asphalt  to  crack  until  after  the 
fourth  or  fifth  rolling.  At  this  stage  most  of  the  coating  had  been 
forced  into  the  voids  of  the  stone,  as  was  found  by  cutting  into 
the  surface,  and  very  little  decrease  in  its  thickness  was  detected 
after  the  rock  had  come  to  a  firm  bearing.  In  this  manner  a  sec- 
tion 385  feet  long  and  18  feet  wide  was  paved. 

The  behavior  of  the  rock  asphalt  varied  according  to  tem- 
perature. During  early  morning,  when  both  asphalt  and  rock 
were  cold,  it  worked  into  hard,  rounded  lumps,  which  were  broken 
with  difficulty  with  the  rakes.  The  location  of  such  lumps  was 
plainly  visible  after  repeated  rolling,  but  they  disappeared  'com- 
pletely after  being  subjected  to  the  heat  of  the  sun.  As  the  day 
grew  warmer  the  material  spread  smoothly  and  compacted  evenly 
and  uniformly.  A  light  but  cold  rain,  with  temperature  of 
65°  F.,  impeded  work  for  several  hours.  After  a  temperature 
of  from  70°  to  75°  F.  was  reached  work  progressed  well 
and  good  results  were  obtained  immediately.  The  temperature 
of  the  days  during  the  period  covered  by  the  work  was  uniform, 
excepting-  at  the  time  of  the  cold  rain  mentioned  above,  with  a 
maximum  temperature  ranging  from  94°  to  97°  F.  during  the 
heat  of  the  day.  The  inadvisability  of  working  the  material  when 
chilled  and  damp  was  apparent,  for  that  portion  of  the  road  laid 
at  a  temperature  of  65°  F.  failed  to  become  hard  and  firm  for 
several  hours  after  subsequent  applications  had  compacted  satis- 
factorily. 

One  difficulty  met  in  this  work  was  caused  by  the  necessity 
for  having  one-half  of  the  roadway  open  to  traffic,  while  the  other 
half  was  under  construction.  In  order  to  avoid  a  break  or  distinct 
line  between  the  parts,  the  inner  edge  of  the  asphalt  was  rolled 
lightly,  so  that  when  the  other  half  of  the  work  was  laid  the  loose 
particles  would  unite  without  difficulty.  As  a  result  of  this  pre- 
caution an  unbroken  surface  along  the  middle  of  the  roadway  was 
secured.  The  ready  cohesion  of  the  particles  was  further  shown 


108  ASPHALTS.  [CHAP.  xv. 

when,  after  an  accident,  it  was  necessary  to  repair  a  portion  which 
had  been  opened  to  traffic  for  three  days.  The  asphalt  and  stone 
were  removed  over  an  area  of  4  square  feet,  the  stone  replaced 
and  tamped  by  hand,  and  a  new  coating  of  asphalt  applied  and 
rolled.  After  two  days  no  evidence  of  damage  or  repair  remained 
visible. 

As  soon  as  one-half  of  the  roadway  had  been  surfaced  and 
properly  rolled  it  was  opened  to  traffic  in  the  hope  that  the  asphalt 
would  be  further  worked  into  the  voids  of  the  stone  by  the  action 
of  wheels  and  hoofs.  At  first  the  coating  rutted  badly  under  the 
weight  of  the  heavy  loads  of  gravel  and  logs  to  which  it  was  sub- 
jected and  the  smooth  surface  given  by  the  roller  was  seriously 
cut  by  hoofs.  This  effect  decreased  visibly  after  three  or  four 
days ;  at  the  end  of  a  week  no  trace  remained  of  the  deepest  ruts 
and  the  surface  had  become  smooth  and  compact.  It  then  pre- 
sented an  appearance  not  unlike  that  of  an  asphalt  pavement 
which  has  been  open  to  traffic  for  some  time.  Close  inspection, 
however,  showed  the  presence  of  a  slight  excess  of  bitumen  which 
held  a  thin  film  of  dust  and  fine  sand  closely  and  caused  it  to  be- 
come incorporated  into  the  surface  under  traffic.  With  the  pass- 
ing of  time  this  excess  of  bitumen  disappeared  and  at  the  end  of 
four  months  very  little  was  noticeable. 

The  conditions  necessary  to  satisfactory  results  from  the  use 
of  rock  asphalt  in  this  form  as  a  binder  in  macadam  road  con- 
struction are :  That  the  broken  stone  of  the  wearing  course  be 
clean  and  dry  to  facilitate  adhesion  of  the  bitumen  and  of  fairly 
uniform  size  and  uncompacted  to  give  a  large  percentage  of 
voids;  that  the  stone  be  spread  evenly  and  true  to  grade;  that 
the  temperature  of  the  atmosphere  be  sufficiently  high  to  cause 
the  bitumen  to  soften  and  allow  the  grains  to  glide  over  each 
other  readily;  that  the  asphalt  be  thoroughly  raked  into  the  voids 
of  the  stone  without  disturbing  the  latter. 

The  simplest  method  of  rolling  rock  asphalt  is  to  have  the 
roller  move  forward  as  far  as  the  work  permits,  returning  with 
but  little  lateral  change  of  course.  Any  great  change  in  the 
course  of  the  roller  accompanied  by  rapid  guiding  movement  of 
the  trunnion  roll  causes  the  loose  asphalt  to  slough  over  the  stone 
surface  and  tends  to  make  it  adhere  to  the  trunnion  roll.  For 
similar  reasons  sudden  starting,  stopping,  and  reversing  are  to 
be  avoided  until  the  material  has  been  thoroughly  compacted.  If 


26 


'A  S  P  H  A  L  T  S' 


DUSTLESS    ROADS.  109 

the  roller  is  driven  upon  newly  spread  material  a  distance  less 
than  its  wheel  base,  at  the  same  time  working  from  the  outside' 
to  the  crown  of  the  road,  the  drive  rolls  may  always  be  kept  upon 
partially  compacted  material.  In  this  manner  the  rolling  may  be 
kept  abreast  of  the  spreading,  little  damage  being  done  in  case 
of  rain  or  sudden  cold,  and  any  defects  in  the  work  will  become 
apparent  as  the  work  progresses. 

The  stone,  labor,  teams,  and  roller  were  furnished  by  the 
county  authorities.  Labor  ranged  from  $1.20  to  $1.25  and  teams 
cost  $3  per  day  of  ten  hours.  The  roller  was  loaned  to  the  county 
for  this  work  and  the  cost  of  operating  it  was  $2.50  per  day  for 
the  engineer  plus  the  cost  of  fuel.  The  water  for  the  roller  was 
taken  free  of  charge  from  the  city  mains,  but  as  a  team  was  kept 
constantly  to  supply  water  and  coal  to  the  roller  this  amount  is 
charged  in  the  item  of  rolling.  About  65  cubic  yards  of  gravel 
was  removed  in  shaping  the  subgrade  and  used  to  repair  the 
gravel  surface  beyond  the  point  where  the  work  stopped.  The 
cost  of  loading  and  hauling  this  material  is  charged  against  the 
asphalt  work,  while  the  spreading,  rolling,  and  sprinkling  of  the 
gravel  is  charged  against  repair  work  in  the  preparation  of  the 
roadway  to  receive  a  treatment  of  oil.  This  item  is  referred  to 
again  in  the  discussion  of  the  cost  of  experiments  in  the  use  of 
oil  as  a  dust  preventive.  The  unit  cost  of  rolling  is  large  in  pro- 
portion to  the  actual  cost  ,of  the  roller  to  the  county,  by  reason 
of  the  short  length  of  road  surfaced.  As  a  consequence  the  roller 
was  frequently  idle,  though  under  steam. 

Two  factors  lent  themselves  to  increasing  the  cost  of  spread- 
ing the  asphalt :  The  inexperience  of  the  laborers  in  working  the 
material,  and  the  long  haul  to  which  it  was  subjected.  The  former 
would  have  been  materially  reduced  after  a  few  days,  but  the 
latter  was  unavoidable  and  resulted  in  packing  the  rock  asphalt 
so  firmly  that  it  required  great  additional  labor  afterwards  to 
break  the  lumps.  The  stone  was  delivered  on  the  roadway  at 
$1.20  per  cubic  yard  and  was  spread  4  inches  thick  uncompacted, 
making  the  cost  per  square  yard  delivered  13  cents.  The  rock 
asphalt  was  donated,  but  is  charged  in  the  following  table  at  its 
market  price  of  $5  per  ton  f.  o.  b.  cars  at  Bowling  Green,  and 
the  cost  of  loading  and  hauling  it  is  included  in  its  unit  cost  de- 
livered on  the  work.  It  was  spread  about  iy2  inches  thick,  or  at 
a  rate  of  24.5  square  yards  per  ton. 


no                                           ASPHALTS.  [CHAP.  xv. 

The  following  table   contains   an  itemized  statement  of  the 
cost  of  the  various  processes  of  the  work: 

TABLE  VIII. 
COST  DATA  OF  ROCK  ASPHALT  EXPERIMENT. 

Cost 

per  square  Percentage 

Item.                                        yard.         Total  cost.  of  total. 

Cents.          Dollars.  Per  cent. 

Shaping   subgrade 5.66               43-6o  n.8 

Stone  on  work 13.71             105.60  28.8 

Spreading   stone .    .78                 5.97  1.7 

Rolling   stone 09                   .67  .3 

Asphalt  on  work 23.77             183.10  50.0 

Spreading  asphalt 1.44               11.06^2  3.1 

Rolling  asphalt 2.18               16.78^  4.3 


Total    47.63  366.79  100.0 

As  has  already  been  stated,  the  finished  road  surface  was 
similar  to  an  asphalt  pavement  which  had  been  open  to  traffic  for 
some  time  in  its  dark-brown  color  and  smooth  even  finish.  Prac- 
tically little  impression  was  made  on  the  surface  by  traffic  after 
a  week,  except  on  very  warm  days,  and  this  was  not  sufficient  to 
impair  its  appearance  or  value.  Incisions  into  the  surface  re- 
vealed a  dense  coating  of  dust  and  sand  about  one-eighth  of  an 
inch  in  thickness  thoroughly  incorporated  in  the  bitumen.  This 
served  at  once  as  a  wearing  surface  and  as  a  protection  to  retain 
the  bitumen  in  the  sand  below.  Only  at  one  or  two  points  did 
the  limestone  of  the  wearing  course  protrude.  This  occurred 
where  the  rock  had  been  disturbed  after  it  had  been  rolled  and 
had  been  forced  up  into  the  asphalt  layer.  Rolling  and  traffic 
had  left  it  flush  with  the  surface,  however,  and  its  presence  was* 
considered  as  a  defect  in  the  appearance  rather  than  in  the  wear- 
ing quality  of  the  roadway. 

After  four  months  the  appearance  of  the  roadway  had  under- 
gone no  appreciable  change.  Along  the  crown  a  few  more  par- 
ticles of  limestone  were  exposed  to  view.  This  was  undoubtedly 
due  in  large  measure  to  the  effect  of  traffic  in  forcing  the  asphalt 


DUSTLESS    ROADS.  Ill 

into  the  voids  of  the  stone,  for  a  large  part  of  the  traffic  is  con- 
fined to  the  center  of  the  pavement.  This  development  was  not 
regarded  as  of  serious  consequence,  however,  as  the  rock  along 
the  axis  of  the  roadway  had  been  more  or  less  disturbed  while 
the  asphalt  was  being  laid,  and  it  is  probable  that  the  few  pro- 
truding stones  were  those  which  had  been  raised  above  the  gen- 
eral plane  of  the  rock  surface  and  were  not  covered  to  the  same 
depth  by  the  rock  asphalt  as  surrounding  rock.  Incisions  into 
the  asphalt  at  this  time  revealed  no  perceptible  loss  by  drying  or 
hardening  of  the  bitumen,  as  the  sand  particles  showed  their 
normal  inclination  to  move  when  warmed  in  the  hand. 

The  permanence  of  macadam  construction  depends  largely 
upon  the  nature  of  the  binder  used  and  the  ability  of  traffic  to 
supply  by  attrition  the  material  which  is  removed  by  wind  and 
water.  It  was  to  test  the  adaptability  of  rock  asphalt  as  such 
binding  material  that  this  piece  of  construction  was  undertaken. 
The  pavement  formed  is  dustless.  There  is  no  appreciable  wear 
of  the  surface  material  to  be  raised  and  carried  away  by  the  wind 
as  dust  and  such  dirt,  as  may  be  carried  upon  it  is  readily  re- 
moved by  sweeping  or  flushing  with  water.  There  is  sufficient 
adhesive  power  in  the  bitumen  to  serve  as  a  cement  to  hold  the 
stone  of  the  wearing  course  in  place,  giving  at  once  a  smooth  and 
waterproof  surface.  It  is  resistant  to  deformation  under  a  load, 
yet  sufficiently  plastic  to  break  the  severity  of  the  blow  from  a 
horse's  hoof,  and  thus,  in  a  measure,  avoids  the  harmful  effects 
of  rigid  pavements  on  animals. 


CHAPTER  XVI. 
METHODS  OF  SURFACING  ROADS. 

STARTING  with  the  more  lasting  and  more  substantial 
methods  of  waterproof  surfacing  of  macadam  roads, 
prominent  mention  must  be  made  of  the  system  which  is  the  re- 
sult of  two  years'  careful  experiments  and  research  made  by 
George  C.  Clausen,  of  the  Sicilian  Asphalt  Paving  Co.,  formerly 
President  of  the  Board  of  Park  Commissioners  in  the  halcyon 
days,  when  the  office  of  Park  Commissioner  was  not  given  as  a 
"political  plum." 

In  the  specifications  of  the  Sicilian  Asphalt  Paving  Co.  for 
roadways  for  heavy  automobile  traffic,  they  first  provide  as  the 
main  supporting  body  a  layer  of  good  sized  clean  stones,  free 
from  all  fine  stuff,  sand,  or  dirt. 

They  roll  this  layer  of  clean  stones  until  they  are  crowded 
firmly  together  and  brought  to  an  even  surface.  They  then  apply 
hot  asphalt  as  a  binder,  filling  the  voids  and  overflowing  the  top 
of  the  layer  to  receive  a  coat  of  small  stones  which,  when  kneaded 
into  the  surplus  asphalt,  forms  the  wearing  surface  of  the  road. 

To  knead  the  small  stones  into  the  asphalt  without  disturb- 
ing the  under  layer,  they  use  a  special  heavy  steam  roller  de- 
signed for  that  purpose. 

Their  method  of  thoroughly  rolling  the  bed  of  coarse  stones 
before  the  asphalt  binder  is  applied  produces  a  strong  and  stiff 
under  layer  which  cannot  be  displaced  or  flattened  out  by  the 
traffic.  This  non-elastic  base  preserves  the  grade  and  crown  of 
the  surface  layer  which  is  anchored  fast  to  it  by  the  asphalt  ex- 
tending through  both  layers. 

The  surface  of  small  stones  and  asphalt  will  always  be  elas- 
tic and  therefore  non-slippery.  The  wear  is  very  little,  the  sur- 
face being  cushioned  by  the  asphalt. 

The  roadway  is  dustless  and  waterproof  and  cannot  be 
washed  out  or  gullied  by  storms.  It  has  its  full  strength  and  is 
ready  for  immediate  use  when  laid. 


la 


c    > 

r> 


• 

IS 


'AS  PH  A  LT  S' 


SURFACING    ROADS.  113 

It  is  preferred  to  use  the  ordinary  commercial  i^-inch  stone 
for  the  under  layer  of  the  road,  including  stones  passing  a  2^/2- 
inch  ring  and  having  all  that  will  pass  a  I  %  -inch  ring  screened 
out  of  it.  For  the  surface,  the  part  screened  out  can  be  used,  pro- 
vided it  is  clean  and  free  from  dirt. 

Any  good  macadamized  road  has  stone  in  it  fit  for  the  pur- 
pose and  can  be  readily  converted  to  this  system,  making  it  dust- 
less  and  automobile-proof  at  comparatively  little  expense. 

In  August,  1906,  there  was  put  down  for  experimental  pur- 
poses over  6,000  square  yards  of  this  roadway  in  Bronx  Park, 
New  York,  near  the  eastern  gate,  where  the  automobile  and 
other  traffic  is  very  heavy.  It  was  put  down  of  various  thick- 
nesses, in  some  places  very  thin  indeed  and  nowhere  more  than 
half  the  thickness  called  for  in  their  present  specifications.  They 
used  various  compositions  of  asphalt  by  means  of  which  they  now 
claim  to  know  exactly  which  is  the  best  to  use. 

After  two  years'  use  this  roadway  now  stands  the  heaviest 
kind  of  automobile  traffic  with  perfect  success,  and  with  remark- 
ably little  wear.  This  example  shows  that  the  automobiles  can- 
not strip  the  surface  layer  even  if  only  a  quarter  of  an  inch  thick; 
that  the  surface  is  non-slippery  and  dustless  and  though  always 
altstic,  that  it  never  forms  into  waves  or  gets  humpy,  but  keeps 
in  perfect  shape  as  to  crown  and  grade. 

The  under  layer  alone  makes  a  good  road  and  will  carry  the 
traffic  for  a  long  time  if  the  road  is  neglected.  Repairs  can  be 
made  at  any  time  without  disturbing  the  surface. 

It  will  be  seen  that  the  construction  of  their  roadway  is 
simple  and  easily  understood  and  that  no  well-established  prin- 
ciple of  roadmaking  is  violated. 

The  specifications  issued  by  this  company  are  as  follows: 

SPECIFICATION. 

The  roadbed  must  be  firm  enough  to  be  finished  to  sub-grade  by  a  10 
to  15-ton  roller. 

The  surface  of  the  roadbed  is  to  be  six  inches  (6")  below  grade.  It 
must  be  closely  compact  and  of  such  a  nature  that  the  macadam  cannot 
be  pressed  into  it  more  than  one  inch  (1")  by  a  10  to  15-ton  roller. 

On  this  roadbed  a  layer  of  one  and  one-half  inch  (!%")  stone  is  to  be 
evenly  spread  to  a  depth  of  six  inches  (6"),  more  or  less,  as  may  be 
needed  to  bring  the  surface  of  the  layer  when  finished  to  within  two  inches 
(2")  of  grade. 

The  stones  used  in  this  layer  must  be  clean  and  free  from  any  fine 
stuff  that  would  act  as  a  binder. 


H4  ASPHALTS.  [CHAP.  xvi. 

It  must  be  thoroughly  rolled  with  a  10  to  15-ton  roller  until  a  firm, 
unbound  surface  is  obtained,  composed  exclusively  of  good-sized  stones 
crowded  together,  face  up,  in  horizontal  alignment. 

The  aligned  surface  of  the  layer  being  carefully  maintained,  it  is  to 
be  flooded  with  hot  "Sicilian  asphalto"  of  a  quality  as  hereinafter  specified, 
so  it  will  flow  into  and  fill  all  the  interstices  and  voids  and  at  the  same 
time  overflow  and  cover  the  surface  of  the  layer  to  a  depth  not  less  than 
three-quarters  (%)  of  an  inch. 

The  Sicilian  Asphalto  is  a  mixture  of  bituminous  ingredients,  carefully 
manipulated  so  as  to  make  a  soft  and  tough  binder,  without  liquifying 
injuriously  in  hot  weather. 

Hudson  River  Road  Gravel,  or  a  mixture  of  three-quarter  inch  (%") 
stone  and  screenings  of  Trap  Rock  must  now  be  evenly  spread  upon  the 
Asphalt,  enough  to  be  used  to  bring  the  surface  of  the  road  to  grade  when 
finished. 

This  material  must  then  be  thoroughly  kneaded  into  the  Asphalt  with- 
out disturbing  the  under  layer,  and  rolled  until  a  smooth,  dustless,  elastic 
surface  is  obtained. 

Another  excellent  device  for  surfacing  macadam  is  that  in- 
troduced by  the  Wadsworth  Stone  and  Paving  Company,  pre- 
viously mentioned  in  the  Public  Roads  Office  reports,  and  is  as 
follows : 

SPECIFICATION. 

The  sub-grade  will  be  brought  to  an  even  surface,  parallel  with  the 
grade  proposed  for  the  pavement,  by  making  the  necessary  excavation 
or  embankment.  Soft  or  spongy  earth,  or  other  material  not  affording  a 
firm  foundation,  will  be  removed,  and  the  space  filled  with  sound  stone, 
which  shall  be  solidified  by  ramming  or  rolling,  as  hereinafter  provided. 
The  sub-grade  surface  will  be  compacted  by  rolling  with  a  roller  operated 
by  steam  power  and  weighing  not  less  than  ten  (10)  tons.  Any  portion 
not  accessible  to  roller  shall  be  thoroughly  compacted  by  ramming.  When 
the  rolling  and  ramming  shall  have  been  done,  the  surface  shall  be 
true  and  smooth  and  eight  (8)  inches  below  the  proposed  finished  surface 
for  the  pavement. 

Upon  the  sub-grade  thus  prepared  shall  be  spread  an  even  layer  of 
sound,  hard  limestone  or  furnace  slag  broken  into  fragments  so  that  the 
largest  diameter  of  any  stone  shall  not  be  over  3".  The  stone  or  slag 
must  be  free  from  clay  or  dirt  and  contain  no  vegetable  or  perishable 
matter.  This  layer  of  stone  or  slag,  after  the  same  has  been  thoroughly 
rolled  shall  be  6"  thick,  and  its  surfaces  shall  be  parallel  with  the 
finished  contour  of  roadway  and  2''  below  same.  This  layer  of  stone 
shall  contain  an  even  and  uniform  amount  of  screenings,  equal  to  twenty- 
five  (25)  per  cent,  of  the  total  amount  of  stone,  so  that  the  stone  can  be 
thoroughly  compacted  in  rolling.  This  layer  of  stone,  if  the  contractor 
sees  fit,  may  be  hauled  upon  the  sub-grade,  and  there  broken  to  the 
required  size. 

Upon  this  layer  of  stone,  prepared  as  described,  there  shall  be  evenly 
spread  a  layer  of  hard,  sound,  clean  limestone,  free  from  screenings,  dust 
or  dirt  crushed  into  fragments  varying  uniformly  in  size  from  one  and 
one-half  (!%")  inches  to  two  and  one-half  (2%")  inches,  measured  on 
longest  diameter. 


SURFACING    ROADS.  115 

This  last  layer  of  crushed  limestone  after  being  uniformly  spread, 
shall  be  rolled  once.  After  said  rolling,  the  top  layer  shal  measure  two 
(2)  inches.  Kentucky  Rock  Asphalt  shall  then  be  hauled  on  the  street  in 
carts  or  wheelbarrows  and  dumped,  after  which  it  shall  be  spread  and 
raked  with  asphalt  rakes,  in  manner  satisfactory  to  the  Engineer.  This 
Kentucky  Rock  Asphalt  shall  be  pulverized  and  shall  contain  not  less 
then  seven  (7)  per  cent,  of  natural  bitumen.  This  top  surface  shall  then 
be  thoroughly  rolled  until  the  interstices  of  the  crushed  stone  are  entirely 
filled  with  Rock  Asphalt,  and  the  surface  of  the  roadway  is  hard  and  even, 
and  entirely  covered  with  Rock  Asphalt;  the  whole  to  be  satisfactory  to 
the  Engineer  in  charge. 

This  work  must  be  done  in  dry  and  warm  weather,  with  the  ther- 
mometer showing,  not  less,  than  70  degrees  F.  If  the  Asphalt  surface 
of  the  street  should  be  damp  or  moist  from  any  cause,  it  shall  not  be 
rolled  until  the  sun  has  thoroughly  dried  the  surface.  Whenever,  after 
one  or  more  rollings,  it  is  found  that  Rock  Asphalt  sticks  to  the  roller, 
the  surface  of  the  street  shall  then  be  dusted  with  hydraulic  cement  to 
the  satisfaction  of  the  Engineer. 

The  Rock  Asphalt  shall  be  so  spread  upon  the  street  that  one  (1)  ton  of 
2,000  Ibs.  will  cover,  not  more,  than  twenty-five  (25)  square  yards. 

The  Good  Roads  Improvement  Co.  have  done  work  in  sev- 
eral sections  of  the  country,  using  a  material  known  as  Asphalt- 
oiline.  This  is  made  from  crude  oil  with  the  heaviest  natural 
asphaltum  base  of  any  oil  west  of  California  and  contains  no  par- 
affine  and  no  sulphur.  It  is  treated  and  refined  to  eliminate  the 
volatile  matters  and  other  constituents  and  is  a  liquid  asphalt 
from  75%  to  95%  pure,  according  to  grades,  and  contains  suffi- 
cient petroleum  to  secure  proper  penetration. 

Their  formula  is  as  follows: 

After  the  road  is  finished  according  to  specifications  for 
macadamizing  to  the  entire  satisfaction  of  your  engineer  we 
agree  to  put  on  a  coat  of  liquid  asphalt  oil  to  be  applied  accord- 
ing to  the  following : 

SPECIFICATION. 

The  prepared  roadbed  shall  be  treated  by  distributing  the  liquid 
asphalt  oil  over  the  surface  of  the  same,  at  the  rate  of  not  less  than 
%  gallon  per  square  yard  by  means  of  a  machine  fitted  with  an  ap- 
pliance for  the  purpose  and  so  arranged  as  to  enable  the  operator  to 
control  the  flow  and  distribute  the  material  equally  and  uniformly,  leaving 
no  streaks  or  spots,  and  also  enable  the  operator  to  cut  out  any  part  or 
section  to  avoid  depositing  a  surplus  of  the  material  on  the  roadway  or 
on  railway  tracks  (if  such  are  located  in  the  roadway),  or  in  the  gutters, 
and  to  completely  control  the  quantity  delivered. 

A  coat  of  50  per  cent,  %-inch  stone  and  50  per  cent,  screenings 
properly  mixed  is  spread  to  a  sufficient  thickness  to  a  smooth  and 
uniform  surface  to  the  road,  then  again  rolled  until  the  road  becomes 
thoroughly  consolidated,  hard  and  smooth.  Any  depressions  formed 


Ii6  ASPHALTS.  [CHAP.  xvi. 

during  rolling  or  from  any  other  cause  are  to  be  filled  in  with  1%-inch 
stone  and  screening  brought  to  the  proper  road  grade  and  curvature  as 
determined  by  the  Engineer. 

The  Indian  Refining  Co.  sell  a  blended  liquid  asphalt  from 
Kentucky — a  manufactured  product  carrying  75  per  cent,  asphalt 
in  solution  fluxed  with  other  constituents  of  a  volatile  nature  ab- 
solutely free  from  paraffine  and  sulphur,  the  preparation  remain- 
ing in  a  fluid  condition  at  a  temperature  above  50  degrees  Fahr- 
enheit, and  is  entirely  free  from  all  the  objectionable  features  of 
crude  oil.  It  carries  a  slight  odor,  not  offensive,  which  disap- 
pears entirely  in  a  period  of  two  to  five  days,  which  is  the  time 
required  for  the  liquid  asphalt  to  properly  set  and  dry  upon  the 
surface  of  the  roadway  upon  which  it  is  applied.  It  is  a  scien- 
tifically prepared  material,  which  was  developed  from  several 
years'  experiment  in  treating  roads  with  crude  oils  for  the  pur- 
pose of  eliminating  dust. 

Petrolithic  pavement  for  city  streets  and  country  roads  is  a 
California  invention.  It  consists  of  natural  soil,  which  to  a  depth 
of  six  inches,  has  been  impregnated  with  crude  asphaltic  oil,  and 
tamped  until  it  is  practically  as  solid  as  stone,  by  means  of  a 
Petrolithic  Rolling  Tamper.  The  tamping  roller  to  be  used  in 
the  execution  of  the  work  consists  of  a  roller  the  outer  surface 
of  which  is  studded  with  teeth  not  less  than  seven  inches  long 
and  having  a  surface  area  of  not  less  than  four  square  inches 
each,  the  roller  itself  is  of  such  a  weight  that  the  load  upon  each 
tooth  is  not  to  be  less  than  three  hundred  pounds. 

In  April,  1905,  the  City  Engineer  of  Los  Angeles,  Cal.,  gave 
the  author  the  following  specifications  for  surfacing  roadways : 

SPECIFICATION. 

Upon  the  surface  prepared  and  brought  to  sub-grade  shall  be  spread 
in  the  following  described  manner:  Two  layers  of  gravel,  of  the  same 
quality  as  that  composing  the  natural  surface  of  the  street,  the  bottom 
layer  to  have  a  thickness  of  five  inches,  and  the  top  layer  to  have  a 
thickness  of  three  inches  after  having  been  rolled.  The  first  layer,  which 
shall  contain  no  stones  larger  than  two  and  one-half  inches  in  greatest 
diameter,  is  to  be  uniformly  spread  upon  the  roadway,  and  well  moist- 
ened. The  gravel  shall  be  well  rammed  for  at  least  one  foot  from  the 
gutters,  should  these  be  paved,  or  if  the  gutters  are  not  paved,  then  one 
foot  from  the  curb.  The  remaining  portion  of  the  roadway  shall  then  be 
rolled  with  a  roller  weighing  not  less  than  250  pounds  to  the  inch  width 
of  tire.  The  rolling  of  the  roadway  shall  commence  at  the  rammed 
portion.  All  depressions  must  be  promptly  filled,  moistened  and  again 
rolled.  The  rolling  must  be  continued  until  the  surface  wil  not  yield 
under  a  roller  of  the  weight  above  described. 


F& 

PS 


28 


"ASPHALTS' 


SURFACING    ROADS.  117 

On  this  surface  shall  be  spread  the  top  layer,  which  shall  be  raked 
free  from  all  stones  larger  than  one-half  inch  in  greatest  diameter.  If 
no  gutters  are  provided,  these  larger  stones  shall  be  raked  to  the  curb 
and  distributed  over  a  strip  two  feet  in  width  next  to  the  curb.  If 
gutters  are  provided  then  these  stones  shall  be  distributed  on  a  strip 
of  two  feet  in  width  next  to  the  gutter.  The  top  layer  of  gravel  shall 
then  be  thoroughly  compacted  by  ramming  and  rolling  in  the  same  man- 
ner as  specified  for  the  first  layer. 

The  entire  surface  between  the  gutter  lines,  if  there  be  gutters,  or 
between  the  curb  lines  if  there  be  no  gutters,  which  shall  have  been 
rendered  perfectly  smooth  and  hard  by  the  process  above  specified,  shall 
then  be  broken  to  a  depth  of  not  less  than  two  inches  by  a  fine  tooth 
harrow,  or  some  similar  apparatus,  dragged  in  every  direction  over  it, 
until  no  part  remains  untouched.  Oil  shall  then  be  even  distributed  over 
the  surface  in  a  volume  equal  to,  but  not  exceeding,  the  amount  the 
surface  of  the  street  will  absorb  in  such  manner  that  no  oil  shall  remain 
on  the  surface. 

After  a  lapse  of  not  less  than  twelve  hours  the  surface  shall  be  again 
harrowed,  and  receive  a  second  application  of  oil.  Any  part  of  the 
street,  upon  which  a  portion  of  the  oil  or  the  residue  thereof  may  be 
seen,  shall  then  be  sprinkled  with  sufficient  sharp  sand  to  absorb  the 
same,  and  any  portions  that  appear  too  dry  shall  receive  a  further  light 
application  of  oil. 

The  entire  surface  shall  then  be  thoroughly  mixed  and  receive  a  light 
covering  of  sand,  and  be  thoroughly  rolled  and  trimmed  until  no  evidence 
of  oil  remains,  except  the  coloring  of  the  gravel. 

The  total  amount  of  oil  used  shall  not  be  less  than  three  gallons  per 
square  yard  of  the  street  surface.  The  oil  used  shall  be  crude  petroleum 
of  a  density  between  11  and  14  degrees  gravity  Baume,  asphaltum  base, 
and  shall  be  applied  at  a  temperature  not  less  than  150  degrees  Fahr. 


CHAPTER  XVII. 

ASPHALTIC    OILS,   THEIR   CLASSIFICATION   AND 
PROPERTIES. 

OILS  as  a  class  are  fatty  organic  substances  derived  from  in- 
numerable sources.  They  may  be  most  conveniently 
divided  under  three  heads,  as  animal,  vegetable,  and  mineral. 
While  oils  of  the  first  two  classes,  have  been  used  to  some  extent 
as  dust  preventives,  mineral  oils  are  by  far  the  most  important, 
and  have  been  most  generally  used  for  this  purpose.  As  animal 
•and  vegetable  oils,  owing  to  their  lack  of  heavy  binding  bases, 
may  be  ranked  as  temporary  binders,  they  may  be  considered  most 
•conveniently  with  the  lighter  mineral  oils  and  emulsions,  which 
will  be  taken  up  later. 

The  value  of  an  oil  as  a  permanent  dust  preventive  lies  in 
the  quality  and  quantity  of  high-binding  bituminous  base  retained 
by  the  road  surface  after  evaportion  of  the  more  volatile  con- 
stituents. The  bases  present  in  petroleums  vary  from  those  of 
almost  pure  paraffin  to  almost  pure  asphalt,  many  being  mixtures 
of  the  two.  While  the  paraffin  oils  are  of  much  more  value  than 
the  asphalt  from  a  commercial  point  of  view,  the  opposite  is  true 
from  the  standpoint  of  their  use  in  dust  suppression.  An  oil 
wholly  paraffin  is  of  value  only  as  a  temporary  binder  or  dust 
layer.  Petroleum  is  a  mixture  of  a  great  number  of  organic  bodies 
known  as  hydrocarbons,  together  with  small  quantities  of  sul- 
phureted,  nitrogenized,  and  oxygenated  compounds.  The  ap- 
proximate composition  of  crude  petroleum  is  ordinarily  deter- 
mined by  distillation,  but  a  knowledge  of  the  residuums  left  after 
distillation  is  of  fare  value  from  the  standpoint  of  dust  sup- 
pression. 

There  are  seven  distinct  oil  fields  in  the  United  States,  which 
yield  oils  differing  in  qualities.  The  Appalachian,  which  includes 
the  States  of  New  York,  Pennsylvania,  West  Virginia,  south- 
eastern Ohio,  and  parts  of  Kentucky  and  Tennessee,  produces 
oils  which  are  known  as  eastern  oils  or  paraffin  petroleums,  and 


ASPHALTIC    OILS.  119 

which  are  therefore  of  use  only  as  temporary  binders  in  dust  sup- 
pression. The  Ohio-Indiana  field  produces  oils  which  are  much 
like  those  of  the  Appalachian  and  are  also  classed  as  paraffin  oils ; 
and  the  same  is  true  of  the  Colorado  oils.  The  Wyoming  oils  vary 
in  character  from  the  lighter  to  the  heavy  asphaltic  oils  which  are 
found  principally  in  California.  The  oils  from  the  California  field, 
while  of  the  most  varied  character,  consist  mainly  of  more  or  less 
dense  asphaltic  hydrocarbons.  None  of  the  components  are  of 
the  paraffin  series,  and,  as  the  percentage  of  asphatlic  residue  in 
these  oils  is  usually  high  and  of  a  good  binding  character,  they 
may  be  considered  the  best  for  use  as  permanent  binders.  Oils 
from  the  Texas  field  are  of  a  mixed  character.  All  of  them  con- 
tain some  paraffin  as  well  as  a  greater  or  less  amount  of  asphaltic 
residue.  Some  have  been  used  successfully  as  dust  preventives, 
while  others  are  unfit  for  this  purpose.  It  is  needless  to  say  that 
their  value  lies  in  the  relative  amounts  of  asphaltic  and  paraffin 
base  contained.  The  Kansas  oil  field,  including  Oklahoma,  pro- 
duces oils  quite  similar  to  those  from  the  Texas  field  and  shows 
a  mixed  paraffin  and  asphaltic  base.  The  Louisiana  field  also 
yields  oils  similar  to  the  Texas.  Some  of  the  wells  in  the  Indiana 
and  K/entucky  fields  have  also  been  successfully  used.  In  gen- 
eral, however,  the  eastern  oils  are  of  the  paraffin  type  and  use- 
less as  permanent  binders;  the  western  oils  are  of  asphaltic 
character  and  of  great  value  as  permanent  binders,  while  the 
southern  oils  are  of  z.  mixed  character,  containing  part  paraffin 
and  part  asphalt  bases,  their  value  as  dust  preventives  lying  in 
the  relative  amount  of  asphalt  base  contained. 

While  crude  oil  has  been  used  to  a  great  extent  in  the  West 
for  the  purpose  of  dust  prevention,  it  is  often  customary  in  the 
East  to  partially  distill  oils  containing  asphaltic  residues  before 
using"  them  in  this  connection.  By  this  means  many  of  the  more 
valuable  constituents  are  recovered  and  the  residual  oils  produced 
have  a  much  better  binding  quality,  owing  to  the  fact  that  they 
contain  a  larger  percentage  of  asphaltic  base.  A  brief  description 
of  the  principal  processes  of  oil  refining  and  of  the  properties  pos- 
sessed by  different  types  of  refined  oils  will  therefore  be  given. 

Crude  petroleum  is  an  only  liquid  of  rather  unpleasant  odor, 
with  a  specific  gravity  ranging  from  0.73  to  0.97,  according  to  the 
locality  from  which  it  is  derived.  It  varies  in  color  from  greenish 
brown  to  nearly  black  and  often  exhibits  a  reddish  brown  or 


120  ASPHALTS.  [CHAP.  xvn. 

orange  color  when  viewed  by  transmitted  light.  It  is  also  some- 
what fluorescent.  Sand  and  water  are  often  mixed  with  the  crude 
oil,  but  these  separate  and  settle  upon  standing  in  the  storage 
tanks.  In  order  to  recover  various  products  from  the  crude  pet- 
roleum, it  is  subjected  to  a  process  of  refining  by  means  of  frac- 
tional distillation  in  a  manner  somewhat  similar  to  that  employed 
for  the  refining  of  crude  coal  tar. 

The  most  valuable  products  are  the  kerosene,  or  burning  oils, 
and  a  method  known  as  ''cracking/'  which  increases  their  yield, 
is  very  generally  employed.  This  is  accomplished  at  a  certain 
stage  of  the  distillation  by  modifying  the  fire  so  that  only  the 
bottom  of  the  still  is  subjected  to  a  great  heat,  while  the  top 
and  sides,  being  exposed  to  the  air,  become  somewhat  cooled. 
By  this  means  the  heavy  oil  vapors  are  condensed  within  the 
the  still  itself,  and  upon  dropping  back  into  the  residium,  which 
is  much  hotter  than  their  boiling  point,  break  up  into  lighter  oils 
with  lower  boiling  points  with  a  separation  at  the  same  time  of 
free  carbon  or  coke,  which  is  deposited  in  the  residium.  Here 
we  have  a  condition  somewhat  similar  to  that  encountered  in 
the  case  of  coal  tar  produced  at  a  high  temperature.  As  the  free 
carbon  is  not  a  binder,  it  is  useless  in  a  dust  preventive,  and 
when  present  in  large  amounts  is  apt  to  produce  the  same  bad 
effects  in  an  oil  as  in  a  tar. 

The  residium  of  the  various  petroleums  have  been  used  to 
a  great  extent  as  fluxes  for  softening  the  solid  native  bitumens  used 
in  the  paving  industries.  Their  various  characteristics  and  prop- 
reties  have  therefore  been  given  considerable  study.  As  the 
character  of  the  residues  present  in  both  the  crude  and  refined 
petroleums  is  of  the  greatest  importance  from  the  standpoint 
of  dust  suppression,  the  results  obtained  from  a  study  of  these 
fluxes  should  be  of  service  in  determining  the  suitability  of  vari- 
ous oils  for  this  purpose.  The  character  of  the  residue  will  nat- 
urally vary  as  the  crude  petroleums  vary,  although,  as  has  been 
shown,  the  method  of  preparation  may  produce  considerable 
effect  upon  the  residue. 

The  paraffin  petroleum  residuums  are  of  a  soft,  greasy  char- 
acter and,  as  their  name  implies,  contain  a  large  amount  of  par- 
affin hydrocarbons  and  paraffin  scale  or  crude  paraffin.  A  road 
surface  treated  with  material  of  this  character  will  be  dustless 
for  the  time  being,  but  in  damp,  rainy  weather  will  become  cov- 


"ASPH  A  LTS' 


ASPHALT1C    OILS.  121 

ered  with  a  slimy,  greasy  mud,  which  is  easily  washed  away  and 
leaves  the  road  is  as  bad,  if  not  wprse,  condition  than  it  was 
before  treatment.  When  the  crude  or  even  the  residual  oil  is 
used  solely  as  a  binder,  it  may  therefore  be  predicted  that  the 
outcome  will  prove  a  failure. 

The  base  held  by  the  California  petroleums  is  composed  of 
bitumens  resembling  asphalt.  The  residium  contains  no  paraffin 
and,  if  cracking  has  not  been  employed  in  its  preparation,  carries 
but  little  free  carbon.  The  specifications  for  California  fluxes 
call  for  not  over  6  per  cent,  fixed  carbon.  Both  the  crude  oil 
and  the  residiums,  if  properly  prepared,  act  as  excellent  binders 
and  have,  as  a  rule,  given  the  best  results  of  any  oils  which  have 
been  used  as  dust  preventives. 

The  semi-asphaltic  oils,  such  as  those  obtained  from  Texas, 
carry  an  aphaltic  base,  but  also  a  considerable  amount  of  paraffin 
hydrocarbons  and  a  little  over  I  per  cent,  of  paraffin  scale.  While 
somewhat  inferior  to  the  California  products,  good  results  have 
often  been  obtained  from  their  use  on  roads  in  both  the  crude 
and  the  refined  state.  Those  which  contain  the  greatest  amount 
of  heavy  binding  bitumens  and  the  least  amount  of  paraffin  scale 
are,  of  course,  to  be  preferred.  In  order  to  obtain  the  best  re- 
sults the  residiuums,  as  well  as  the  crude  oils  of  asphaltic  or 
semi-asphaltic  character,  should  be  comparatively  free  from  water. 

Sometimes  the  residues  from  the  distillation  of  petroleum, 
while  yet  hot,  are  subjected  to  the  action  of  a  jet  of  air,  which 
has  a  tendency  to  thicken  or  harden  them.  It  is  doubtful,  how- 
ever, if  an  oil  thus  treated  will  be  improved  for  use  as  a  dust 
preventive,  as  the  life  of  the  oil  is  apt  to  be  destroyed  and  its 
lasting  qualities  as  a  binder  lessened. 

The  use  of  a  paraffin  petroleum  is  to  be  avoided,  as  a  good 
crude  product  is  to  be  preferred  to  a  badly  cracked  residiuum 
or  one  produced  from  a  poor  quality  of  crude  petroleum.  Con- 
siderable attention  has  been  paid  to  the  actual  quality  of  oils 
which  have  been  employed  as  dust  preventives.  A  number  of 
specially  prepared  or  refined  oil  products  are  now  on  the  market 
for  use  on  roads,  both  in  the  form  of  residiuums  and  emulsions. 
The  residuum  products  have  been  prepared  from  asphaltic  or 
semi-asphaltic  oils  by  methods  similar  to  those  described,  while 
the  emulsions  are  usually  residuums  which  have  been  treated  with 
saponifying  agents  in  order  to  make  them  miscible  with  water. 


122  ASPHALTS.  [CHAP.  xvn. 

Owing  to  the  fact  that  oils  from  a  number  of  wells  are  com- 
monly run  through  the  same  pipe  lines  from  the  wells  to  the 
storage  tanks,  it  is  often  difficult  to  obtain  two  lots  of  oil  having 
exactly  the  same  properties,  even  when  purchased  from  the  same 
source.  It  is  very  important,  therefore,  that  an  examination  of 
each  lot  of  oil  be  made  before  attempting  to  use  it  for  the  pur- 
pose of  dust  prevention.  Sometimes  a  partial  chemical  analysis 
is  necessary,  but  in  the  majority  of  cases  a  few  simple  tests  will 
determine  its  suitability  for  this  purpose.  These  methods  of  ex- 
amination are  described  later.  It  is  also  a  wise  measure  to  ex- 
amine residuums  even  when  they  are  especially  advertised  as 
road  preparations,  for,  as  has  been  stated,  there  is  a  strong 
tendency  among  refiners  to  crack  their  oils  in  order  to  increase 
the  yield  of  illuminants,  and  when  this  is  done  the  value  of  the 
residiuum  for  the  purpose  of  dust  prevention  will  be  considerably 
lessened.  If  the  road  engineer  understands  thoroughly  the  prop- 
eties  possessed  by  the  oil  which  he  is  handling,  he  will  be  able 
to  avoid  many  dismal  failures  which  might  otherwise  occur. 

Some  of  the  results  obtained  from  an  examination  of  vari- 
ous crude  and  refined  petroleums  in  the  New  York  Testing  La- 
boratory are  given  in  the  following  tables  in  order  to  show  the 
differences  in  properties  possessed  by  the  different  kinds  of  ma- 
terial. They  do  not  in  any  sense  represent  absolute  values  for 
the  different  classes  of  oils,  but  will  serve  to  give  a  general  idea 
of  the  relative  characteristics  of  each. 

TABLE  IX. 
RESULTS  OF  TESTS   OF  CRUDE   PETROLEUMS. 

Volatil-  Volatil-  Volatil- 

Flash-  ity  at       ity  at  ity  at 
Specific    ing    110°  C.,  160°  C.,  205°  C., 

Kind   of   oil.                              gravity,  point.    7  hrs.      7  hrs.  7  hrs.      Residue. 

°C.        %             %  %             % 

Pennsylvania,  paraffin 0.801      (a)        47.3        58.0  68.0        b32.0 

Texas,  semi-asphaltic 904         43      20.0        27.0  49.0        c51.0 

California,  asphaltic   939          26       d42.7        e57.3 

aOrdinary  temperature.  cQuick  flow. 

bSoft.  dVolatility  at  200°,  7  hrs. 

eSoft  maltha;  sticky. 

It  will  be  noticed  from  the  foregoing  results  that  in  the 
samples  examined  the  specific  gravity  increases  from  the  paraffin 
to  the  asphaltic  oil.  This  is  also  true  of  the  percentage  of  resi- 
due, while  the  volatility  decreases  correspondingly.  The  residues 


ASPHALTIC    OILS.  123 

range  in  character  from  soft  and  probably  greasy  through  an 
intermediate  and  but  slightly  viscous  stage  to  the  more  or  less 
liquid  maltha  of  good  adhesive  properties.  A  rough  idea  of  the 
character  of  these  bases  may  be  formed  by  rubbing  a  little  of 
the  residue  or  even  of  the  crude  oil  between  the  finger  and  thumb. 
Those  of  a  paraffin  nature  will  feel  greasy,  while  those  of  an 
asphaltic  character  will  often  exhibit  an  adhesiveness  which  is 
easily  distinguishable.  The  color  and  odor  will  also  indicate  the 
character  of  the  crude  material  to  those  familiar  with  the  different 
varieties.  In  comparing  the  Pennsylvania  with  the  Texas  oil, 
it  will  be  seen  that  the  former  carries  a  higher  per  cent,  of  light 
oils  than  the  latter.  A  comparison  of  the  residuums  obtained 
from  refining  oils  similar  to  those  described  in  the  above  table 
is  shown  in  the  following  table: 

TABLE!  X. 
RESULTS  OF  TESTS  OF  PETROLEUM  RESIDUUMS. 

Volatil- 
Flash-  ity  at 

Specific    ing    200°  C.,  Solid  Fixed 

Kind   of  oil.                             gravity,  point.   7hrs.  Residue,  paraffin,  carbon. 

°C.        %  %             %  % 

Pennsylvania,    paraffin    0.920        186      14.2  a85.8        11.0  3.0 

Texas,  semi-asphaltic 974       214        6.2  a93.8           1.7  3.5 

California,  asphaltic    1.006        191      17.3  a82.7           0.0  6.0 

aSoft. 

In  comparing  these  results  an  increase  in  specific  gravities 
in  the  same  direction  as  in  the  case  of  the  crude  petroleums  will 
be  noticed.  The  volatility  and  percentage  of  residue,  however, 
are  not  in  the  same  order.  As  these  are  dependent  entirely  upon 
the  point  at  which  distillation  is  stopped  in  the  process  of  re- 
fining, such  a  result  is  to  be  expected.  The  percentage  of  solid 
paraffins  is  found  to  decrease  to  zero  as  the  character  of  the  oil 
becomes  asphaltic.  Only  n  per  cent,  was  found  in  this  particular 
sample  from  Pennsylvania,  but  it  is  not  uncommon  for  oils  of 
this  nature  to  carry  as  high  as  33  per  cent,  paraffin.  The  amount 
of  fixed  carbon  is  found  to  increase  with  the  asphaltic  character 
of  the  oil,  and  this  fact  is  quite  general,  owing  to  the  greater 
tendency  of  the  asphaltic  oils  to  crack  during  distillation. 

In  comparing  the  crude  oils  with  the  residuums,  it  will  be 
seen  that  the  latter,  as  would  naturally  be  supposed,  carry  a 
greater  percentage  of  residue,  and,  other  things  being  equal,  are 


124  ASPHALTS.  [CHAP.  xvn. 

therefore  of  more  value  as  permanent  binders.  A  considerable 
difference  is  also  seen  to  exist  between  their  flash  points,  which 
is  the  temperature  at  which  their  most  volatile  products  flash 
when  brought  in  contact  with  a  flame.  As  a  general  rule,  it  is 
not  difficult  to  distinguish  between  a  crude  and  a  residual  oil, 
but  in  cases  where  any  doubt  may  exist  the  flash  point  is  a  fairly 
accurate  indicator.  Thus,  in  the  case  of  the  crude  Texas  oil  and 
the  Pennsylvania  residuum,  we  find  that  their  specific  gravities 
are  quite  close  together,  and  some  doubt  might  exist  as  to  which 
was  crude  and  which  residual.  A  determination  of  their  flash 
points  would  at  once  settle  this  question. 


30 


"ASPHALT 


CHAPTER  XVIII. 
APPLICATION    OF    ASPHALTIC    OILS. 

MANY  valuable  facts  have  been  learned  in  regard  to  the 
application  of  oils  to  road  surfaces,  although,  owing  to 
contradictory  results,  considerable  differences  in  opinion  seem 
to  exist  as  to  the  actual  and  relative  values  of  different  kinds  of 
oils  under  the  same  conditions  and  under  varying  conditions. 
This  is,  to  a  great  extent,  due  to  lack  of  knowledge  in  regard  to 
the  properties  of  the  material  used  and  to  the  fact  that  climatic 
conditions  and  the  character  of  the  road  treated  have  a  much 
more  important  bearing  upon  the  results  than  is  usually  realized. 

The  subject  of  oil  application  has  received  considerably  more 
study  in  our  country  than  has  been  given  it  by  European  nations. 
It  is  true  that  various  experiments  have  been  carried  on  in  Eng- 
land and  France  with  a  number  of  different  oils,  but  owing  to 
the  lack  of  a  proper  base  in  these  oils  the  results  have  been  dis- 
couraging. Shale  oils  and  Russian  petroleum  residuums,  known 
as  "masut"  or  "astatki,"  have  been  employed,  as  well  as  certain 
vegetable  oils,  such  as  oil  of  aloes.  They  have  all  been  found 
effective  as  temporary  dust  preventives,  but  in  rainy  weather 
produce  a  greasy,  disagreeable  mud  and  soon  disappear  from  the 
road  surface.  The  best  results  have  so  far  been  obtained  with 
heavy  oils  applied  in  the  form  of  a  spray  while  hot. 

As  the  application  of  the  temporary  binders  or  lighter  oils 
can  best  be  considered  in  connection  with  that  of  oil  emulsions, 
the  application  of  the  heavier  oils  only  will  be  taken  up  here. 
Crude  petroleum,  as  well  as  residuums  and  specially  prepared 
oils,  have  been  used  with  more  or  less  success  on  earth  and 
gravel  roads,  as  well  as  on  stone  roads. 

APPLICATION  TO  MACADAM  SURFACES. 

In  applying  oil  to  a  macadam  surface,  holes  and  inequalities 
should  be  repaired ;  it  has  not  been  found  necessary  to  remove  all 


126  ASPHALTS.  [CHAP.  xvm. 

dust  from  the  road  surface,  but  sticks,  leaves  and  other  detritus 
fo  an  organic  nature  should  be  removed. 

The  crude  or  refined  oil  may  be  applied  either  cold  or  hot, 
according  to  its  viscosity  and  ability  to  penetrate  the  road  sur- 
face. The  application  of  cold  oil  is  considerably  the  cheaper  and 
is  to  be  preferred  on  that  account.  Most  crude  oils  and  some  of 
the  lighter  residuums  have  been  used  in  this  way  with  good  results, 
but  it  has  been  found  necessary  to  heat  the  heavier  products  be- 
fore application. 

If  much  work  of  this  kind  is  to  be  carried  on  in  one  locality, 
it  is  sometimes  the  custom  to  erect  a  stationary  heating  plant  at 
a  convenient  railroad  siding.  A  plant  of  this  sort  has  been  de- 
scribed in  a  previous  publication,*  and  consists  of  a  receiving  tank 
of  one  tank-car  capacity  placed  preferably  so  that  the  oil  may  be 
run  in  by  gravity  from  the  car.  A  heating  tank  set  at  an  elevation 
sufficient  to  allow  the  hot  oil  to  run  into  the  distribuing  wagons 
and  fitted  with  steam  coils  through  which  superheated  steam  may 
be  forced  is  placed  near  the  receiving  tank.  The  oil  may  be 
pumped  into  this  heating  tank  as  required  and  heated  to  any  de- 
sired temperature.  Very  often  the  heating  is  carried  on  in  the 
tank  car,  and  the  hot  oil  run  directly  into  the  distributing  wagon. 
When  sufficiently  fluid,  it  can  then  be  applied  to  the  road  by  means 
of  a  large  pipe  and  broomed  into  the  surface  in  the  same  manner 
as  tar.  Patented  distributing  devices  have  been  employed  which 
can  be  attached  to  almost  any  form  of  tank  wagon  and  which,  if 
the  oil  is  fluid  enough,  will  do  away  with  the  necessity  of  broom- 
ing. An  oil  applied  by  this  means  will,  however,  have  to  be  heated 
to  a  higher  temperature  than  in  the  former  case,  as  the  openings 
in  the  distributer  are  of  small  dimensions  and  will  not  allow  the 
oil  to  pass  freely  if  it  is  in  a  very  viscous  state. 

The  main  object  is  to  obtain  an  even  coating,  which  shall  be 
well  absorbed  by  the  road  surface.  The  application  of  a  large 
excess  of  oil  should  be  avoided,  as  it  is  sure  to  make  the  surafce 
sticky  and  disagreeable.  A  covering  of  sharp  sand  or  one-half- 
inch  stone  screenings  should  be  applied  after  the  oil  has  been  al- 
lowed to  penetrate  as  much  as  possible,  in  order  to  take  up  all 
excess,  and  the  surface  thus  formed  should  be  rolled  until  well 
compacted,  additional  sand  or  screenings  being  thrown  on  where- 


*Use  of  Mineral  Oil  in  Road  Improvement,  Yearbook  Dept.  Agric.,  1902   p 
446. 


APPLICATION    OF    ASPHALTIC    OILS.  127 

ever  the  oil  shows  a  tendency  to  force  its  way  to  the  surface  and 
produce  a  sticky  condition.  Sometimes  two  or  three  courses  of 
oil  and  screenings  are  applied.  It  is  usually  considered  better  to 
allow  the  freshly  oiled  road  to  dry  out  to  some  extent  before 
applying  the  top  dressing,  but  in  cases  where  it  is  impossible  to 
keep  traffic  away  the  same  methods  may  be  employed  as  in  the 
case  of  tar,  i.  e.,  either  one-half  the  width  of  the  road  may  be 
treated  at  one  time  or  the  sand  or  screenings  may  be  applied  at 
once.  If  the  oil  is  well  absorbed  it  is  not  always  necessary  to  em- 
ploye the  roller,  as  ordinary  traffic  will  consolidate  the  surface  in 
the  course  of  time. 

APPLICATION  DURING  CONSTRUCTION  OF  MACADAM 

ROAD. 

The  application  of  oil  during  process  of  construction  has  been 
carried  on  with  the  greatest  success  in  California,  where  the  heav- 
iest asphaltic  oils  are  found.  The  residuums  obtained  from  the 
partial  distillation  of  these  oils  have  so  far  given  the  best  results 
when  properly  applied.  The  treatment  is  essentially  the  same  as 
with  tar,  the  object  being  to  build  a  road  containing  a  low  percent- 
age of  voids,  so  that  the  oil  will  act  as  a  binder  only  and  the  strain 
of  traffic  be  borne  by  the  road  stone.  Considerable  attention  should 
be  paid  to  proper  drainage  of  the  road,  as  it  is  essential  that  the 
foundation  be  perfectly  dry.  The  macadam  is  built  in  the  usual 
manner  and  each  course  thoroughly  rolled  until  the  whole  road 
is  well  consolidated.  If  water  is  used  during  the  process  of  con- 
struction sufficient  time  should  be  given  for  the  road  to  become 
perfectly  dry  before  applying  the  oil.  The  hot  oil  is  applied  by 
means  of  a  tank  wagon  fitted  with  a  distributing  device  which 
insures  an  even  distribution.  Any  excess  of  oil  is  taken  up  by  the 
application  of  a  sufficient  covering  of  sand  and  screenings,  and 
the  road  is  then  opened  to  traffic. 

A  road  constructed  in  this  manner  will  usually  require  from 
y^  to  13^  gallons  of  oil  per  square  yard,  depending  upon  the  qual- 
ity of  oil  employed  and  kind  of  road  surface  treated. 

The  softer  and  more  porous  rocks,  such  as  limestone,  permit 
of  a  better  penetration  than  the  harder  rocks,  such  as  trap  and 
granite,  but  good  results  have  been  obtained  by  the  use  of  both 
kinds.  Oils  as  a  class  seem  to  penetrate  better  than  tars,  as  they 
do  not  harden  as  quiclky  upon  exposure  to  the  air.  In  order  to 


128  ASPHALTS,  [CHAP.  xvm. 

keep  the  road  in  proper  condition,  repairs  should  be  made  as  often 
as  necessary,  and  in  the  same  manner  as  in  the  case  of  tars.  By 
this  means  rapid  disintegration  will  be  prevented,  which  would 
otherwise  occur  if  water  were  allowed  to  accumulate  in  the  worn 
places. 

APPLICATION  TO  GRAVEL  ROADS. 

A  gravel  road  is  oiled  in  much  the  same  way  whether  it  is  an 
old  road  or  one  under  construction,  as  only  the  upper  course  is 
treated  in  either  case.  It  is  especialy  important  in  a  road  of  this 
kind  that  the  drainage  be  good,  and  this  matter  should  be  attended 
to  first  of  all.  Any  holes  or  pockets  which  may  exist  should  be 
cleared  out,  if  much  fine  material  is  present,  and  filled  with  clean, 
fresh  gravel,  so  that  the  surface  of  the  road  will  be  uniform  when 
the  patches  have  been  sprinkled  and  rolled.  If  the  lateral  drain- 
age is  bad,  the  entire  surface  should  be  loosened  and  brought  to 
proper  grade  and  crown  by  the  addition  of  new  material  before 
the  oil  is  applied.  In  this  case  more  oil  will  be  required  to  effect 
a  good  bond  than  if  the  old-compacted  surface  was  treated,  but  the 
results  will  be  of  a  more  lasting  character.  The  oil  may  be  applied 
either  cold  or  hot,  according  to  its  viscosity,  by  any  of  the  methods 
already  described.  It  should  contain  a  high  percentage  of  good 
asphaltic  base,  or  otherwise  the  material  near  the  surface  will  be- 
come loose,  owing  to  the  lubricating  qualities  of  the  oil.  The  use 
of  too  much  oil  should  be  especially  avoided,  and  all  excess  should 
be  taken  up  by  the  addition  of  fresh  gravel.  Where  the  surface 
treated  is  loose  and  contains  a  considerable  amount  of  clay,  the  oil 
may  be  worked  into  the  upper  course  by  raking,  which  insures  an 
equal  distribution.  After  application  of  the  oil,  the  road  should  be 
rolled  until  properly  compacted,  and  as  this  is  apt  to  bring  some 
of  the  oil  to  the  surface,  fresh  material  should  be  added  where 
necessary.  If  the  freshly  oiled  road  is  not  well  rolled,  the  action 
of  traffic  will  bring  the  oil  upward ;  a  soft  spongy  surface  condition 
will  be  produced;  loose,  oily  particles  will  be  thrown  out  by  rap- 
idly moving  vehicles;  and  the  oil  will  be  tracked  by  pedestrians. 

Oil  is  applied  to  a  gravel  road  during  construction  in  a  man- 
ner quite  similar  to  that  already  described,  but  certain  points  in 
regard  to  the  method  of  construction  should  be  noted.  These  facts 
are  well  presented  by  the  Commissioner  of  the  Department  of 
Highways  of  California*  in  a  report  which  contains  specifications 


*Biennial  report,  1906. 


WILLETT'S    ROAD    (OILED),    LONG   ISLAND,    N.    Y. 
Oiled  with   Gulf  Refining  Company   (Asphaltum)   Road  Oil. 


APPLICATION    OF    ASPHALTIC    OILS. 


129 


used  in  certain  parts  of  that  State  for  the  construction  of  oiled 
graveled  streets.  As  California  has  been  most  successful  in  this 
kind  of  work,  a  study  of  the  methods  used  there  should  be  of  great 
value  to  experimenters  in  other  localities.  Certain  portions  of 
these  specifications  in  condensed  form  are  given  below  for  the 
purpose  of  emphasizing  the  most  essential  points. 

Before  placing  the  gravel  the  subsurface  must  be  brought  to 
grade  and  rolled.  Upon  this  subsurface  two  layers  fo  good  gravel 
should  be  applied,  the  bottom  layer  having  a  thickness  of  5  inches 
and  the  top  a  thickness  of  3  inches  after  being  rolled.  The  first 
layer  should  contain  no  stones  larger  than  2^2  inches  in  greatest 
diameter  The  gravel  must  be  uniformly  spread  on  the  roadway 
and  well  moistened,  rammed  i  foot  from  the  gutter  or  curb,  and 
the  remaining  portion  rolled  with  a  roller  of  the  type  before 
specified.  All  depressions  must  be  promptly  filled,  moistened,  and 
again  rolled,  the  rolling  being  continued  until  the  surface  will  not 
yield  under  the  roller.  On  this  surface  the  top  layer  of  gravel,  free 
from  all  stones  larger  than  i  inch  in  greatest  diameter,  should  be 
applied  and  compacted  in  the  same  manner  as  the  first  layer.  Oil 
should  then  be  evenly  distributed  over  the  entire  surface  at  the 
rate  of  one-half  gallon  per  square  yard,  and  covered  with  clean, 
sharp  sand  until  no  oil  can  be  seen.  After  the  lapse  of  not  less 
than  twelve  hours,  another  application  of  oil  should  be  made  and 
sand  distributed  in  the  same  manner  and  the  whole  surface  rolled 
until  unyielding  to  the  roller,  as  before  described. 

These  specifications  require  that  the  oil  be  crude  and  that  it 
be  applied  at  a  temperature  not  less  than  150°  F.  nor  above  190° 
F.  Certain  methods  of  testing  the  properties  of  the  oil  are  included 
in  the  specifications,  and  a  consideration  of  these  tests  will  be 
found  later.  In  regard  to  measuring  the  petroleum,  however,  it 
may  be  said  that  the  volume  at  60°  F.  is  taken  as  normal,  and  a 
deduction  of  o.i  per  cent,  is  made  for  every  10°  increase  over  this 
normal  temperature  as  a  correction  for  expansion  by  heat. 

USE  OF  OIL  ON  EARTH  ROADS. 

The  use  of  oil  on  earth  roads  was  first  tried  in  this  country 
in  California.  Crude  petroleum  was  sprinkled  upon  the  road  for 


130  ASPHALTS.  [CHAP.  xvm. 

the  purpose  of  laying  the  dust  only.  It  proved  to  be  a  very 
effective  dust  layer,  and  in  some  cases  improved  the  condition  of 
the  road  surface  to  such  an  extent  that  popular  attention  was 
aroused,  and  as  a  result  many  experiments  were  made  with  a  view 
not  only  to  laying  the  dust,  but  to  hardening  the  surface.  Since 
then  oil  has  been  used  with  varying  success  and  failure,  and  much 
valuable  information  has  been  derived  from  the  experiments.  Cali- 
fornia is  particularly  favored  for  work  of  this  nature,  owing  to  its 
climate  and  the  character  of  its  roads,  as  well  as  to  the  excellent 
road-building  properties  of  its  oils.  Although  it  is  impossible  to 
duplicate  these  conditions  in  other  localities,  the  lessons  learned 
from  the  numerous  experiments  conducted  in  this  State  are  of 
great  interest  as  offering  suggestions  for  work  of  a  similar  nature 
in  other  places. 

It  has  been  found  that  the  character  of  the  soil  plays  a  most 
portant  part  in  the  results  obtained,  and  different  kinds  of  soils 
have  to  be  treated  in  different  ways.  Alkali  soils  disintegrate  the 
oil  and  destroy  its  binding  qualities.  A  sandy  loam  is  the  most 
suitable  for  treatment,  and  almost  invariably  gives  good  results 
when  treated  in  the  proper  manner  with  an  oil  of  good  binding 
quality.  From  a  physical  standpoint  clay  is  probably  the  worst 
of  all,  as  it  does  not  absorb  the  oil  well  and  exhibits  a  tendency  to 
ball  up  and  give  trouble.  Sand  should  therefore  be  added  to  the 
clayey  surface  until  this  difficulty  is  overcome.  As  in  the  case  of 
gravel  roads,  special  attention  should  be  paid  to  drainage,  and  the 
roadbed  should  be  dry  when  the  oil  is  applied.  If  the  foundation 
is  water-soaked,  it  soon  loses  its  ability  to  support  the  surface 
properly,  which  will  then  break  through  in  weak  spots. 

The  use  of  too  much  oil  should  be  avoided,  as  it  will  produce 
a  spongy  surface  condition  and  increase  the  draft  of  vehicles  to  a 
considerable  extent.  It  is  most  important  to  keep  a  road  thus 
treated  in  good  repair.  Whenever  a  rut  or  hole  develops  it  should 
be  cut  out,  oil  should  be  poured  in,  and  it  should  be  filled  up  with 
good  earth  or  sand.  The  loose  material  should  then  be  thoroughly 
tamped  until  even  with  the  surrunding  surface. 

Besides  the  method  of  oiling  earth  roads  already  described, 
another  has  recently  been  employed  with  considerable  success  in 
California.  This  mthod  differs  from  the  other  in  two  essential 
particulars.  The  first  of  these  is  that  water  is  applied  during  the 
process  of  oiling,  and  the  second  that  consolidation  is  produced  by 


APPLICATION    OF    ASPHALTIC    OILS.  131 

a  special  tamping  device.  The  method  has  given  satisfactory  re- 
sults with  sand  and  clay  roads,  as  well  as  with  loam  and  gravel, 
and  is  conducted  as  follows : 

The  road  is  first  plowed  up  to  the  depth  of  6  inches  and  prop- 
erly crowned.  All  clods  and  lumps  are  then  thoroughly  broken 
up  by  means  of  a  harrow,  and  the  roadway  is  well  sprinkled  with 
water.  A  specially  constructed  rolling  tamper  is  then  used  by 
which  the  lower  portion  of  the  loose  earth  is  compacted  to  a  depth 
of  about  2  inches,  except  in  cases  where  the  subgrade  is  unusually 
firm. 

After  the  lower  portion  is  made  firm  by  this  means  a  heavy 
asphaltic  oil  is  applied  at  the  rate  of  about  iy2  gallons  per  square 
yard,  and  a  cultivator  is  passed  over  the  road  until  the  oil  and 
earth  are  thoroughly  mixed.  The  tamper  is  then  used  again,  and 
the  road  is  further  compactd  until  only  ij/2  inches  of  loose  mateiial 
remain  on  top.  This  is  lightly  harrowed  and  sufficient  water  is 
added  to  moisten  it.  Oil  is  again  applied,  and  the  surface  is  rolled 
with  the  tamper  until  firm,  and  finally  it  is  ironed  down  with  an 
ordinary  roller  additional  applications  of  earth  bein  made  wher- 
ever necessary  to  take  up  any  excess  of  oil. 

A  road  constructed  in  this  manner  will  require  from  2y2  to  3 
gallons  of  oil  per  square  yard.  It  is  hard  and  dustless  and  resem- 
bles asphalt. 

The  California  oils  are  best  adapted  for  this  method  of  road 
building,  but  the  cost  of  transportation  to  the  Eastern  States  at 
the  present  time  raises  the  price  to  a  prohibitive  figure.  The 
Texas  and  some  of  the  Kentucky  oils  are  the  best  available  for 
these  localities,  and  range  in  price  from  about  4  to  8  cents  per 
gallon,  according  to  locality.  The  residuums  and  special  prepara- 
tions vary  from  2  to  12  cents  per  gallon.  It  is  impossible  to  esti- 
mate cost  of  application  except  for  individual  cases. 

All  kinds  of  properly  oiled  roads  are  dustless,  noiseless,  water- 
proof, and  resilient,  and  offer  but  little  resistance  to  traffic.  The 
crude  oils  have  a  rather  unpleasant  odor,  which  soon  passes  away. 
Both  the  crude  and  residual  oils  exhibit  a  somewhat  weak  germi- 
cidal  action.  If  an  excess  of  oil  is  present  upon  the  road  surface, 
an  oiled  mud  is  formed  in  wet  weather  which  is  damaging  to 
clothes  and  the  paint  on  vehicles,  but  this  condition  is  not  met  with 
if  the  proper  amount  of  the  right  kind  of  oil  is  employed. 


132  ASPHALTS.  [CHAP.  xvm. 

WATER  AND  SALT  SOLUTIONS. 

The  temporary  binders  as  previously  defined  are  materials 
which  have  to  be  applied  at  more  or  less  frequent  intervals  in  order 
to  suppress  dust.  Their  primary  object  is  to  lay  the  dust  only, 
although  they  may  also  tend  to  preserve  the  road  from  wear.  No 
distinct  line  can  be  drawn  between  the  permanent  and  temporary 
binders,  but  in  general  the  latter  class  may  be  said  to  embrace 
water,  salt  solutions,  the  lighter  oils  and  tars,  and  various  emul- 
sions. 


SPECIFICATIONS  FOR  MINERAL  OILS  TO  BE  USED  AS 
DUST  PREVENTIVES  OR  ROAD  PRESERVATIVES. 

As  oils  may  be  used  on  almost  any  kind  of  road  either  as 
temporary  or  permanent  binders,  their  requisite  qualities  will  de- 
pend upon  the  use  to  which  they  will  be  put.  Almost  any  asphaltic 
or  semi-asphaltic  oil  will  prove  satisfactory  as  a  temporary  binder 
if  properly  applied  either  in  the  form  of  an  emulsion  or  in  its 
natural  state.  Specifications  for  the  properties  of  permanent  bind- 
ers only  will  therefore  be  considered. 

According  to  Ellery  a  good  road  oil  should  contain  at  least 
40  per  cent,  of  commercial  "D"  grade  asphalt,  having  a  penetra- 
tion of  60°  and  no  more  than  3  per  cent,  of  foreign  matter  and 
water.  When  employed  in  the  construction  of  oiled  graveled 
streets  at  Los  Angeles,  Cal.,  the  following  specifications*  were 
adopted  for  crude  oil: 

The  specific  gravity  shall  not  be  lower  than  10°  (i.ooo)  nor 
higher  than  11°  Baume  (0.993). 

All  crude  petroleum  shall  contain  not  less  than  70  per  cent. 
"D"  grade  asphalt,  California  standard. 

All  crude  petroleum  shall  be  tested  for  water  and  sediment. 
Deductions  for  water  and  sediment  in  crude  petroleum  will  be 
made  in  exact  proportion  to  the  percentage  of  such  water  and 
sediment  found. 

In  the  construction  of  asphaltic  oiled  and  tamper-rolled  dirt 
roads  at  Santa  Monica,  Cal.,  the  following  characteristics  were 
specified : 

*Biennial  Report  of  the  Dept.  of  Highways  of  California,  1906,  p.  44. 


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APPLICATION    OF    ASPHALTIC    OILS.  133 

The  oil  shall  be  from  12°  to  14°  Baume  (0.986-0.972)  test 
at  a  temperature  of  60°  F.  and  contain  not  less  than  70  per  cent, 
of  pure  liquid  asphaltum,  natural  non-processed  oil  to  be  subject  to 
gasoline  test  for  water  and  foreign  matter,  and  not  to  contain  over 
2  er  cent,  of  water  or  foreign  matter. 

From  experiments  conducted  by  the  Office  of  Public  Roads 
it  would  seem  that  only  reduced  or  residual  oils  are  apt  to  prove 
satisfactory  as  permanent  binders  if  they  are  semi-asphaltic  in  char- 
acter. The  following  specifications  are  therefore  suggested  for 
this  class  of  oils : 

1.  The  oil  shall  have  a  specific  gravity  of  not  less  than  0.95. 

2.  Its  flash  point  shall  be  not  lower  than  300°  F. 

3.  It  shall  be  free  from  water  as  determined  by  the  gasoline 
test. 

4.  When  heated  to  400°  F.  in  the  manner  previously  described 
for  seven  hours  its  loss  in  weight  should  not  be  over  35  per  cent. 
The  character  of  the  residue  should  be  smooth  and  nearly  solid 
when  cold,  but  not  so  hard  that  it  may  not  be  easily  dented  with 
the  finger,  and  when  soft  it  should  pull  to  a  long,  thin  thread. 

5.  The  oil  shall  be  soluble  in  carbon  disulphide  to  the  extent 
of  98  per  cent.,  and  in  88°  naphtha  to  at  least  88  per  cent. 

The  methods  of  examination  and  specifications  for  asphalt  and 
other  solid  materials  have  not  been  considered  in  this  chapter  for 
obvious  reasons.  They  belong  to  works  on  the  subject  of  pave- 
ments. In  conclusion  it  may  be  said  while  specifications  for  dust 
preventives  and  road  preservatives  should  prove  of  great  service 
in  most  cases  in  securing  proper  materials  they  are  of  no  value 
unless  the  proper  method  of  applying  the  material  to  the  road  is 
employed.  So  far  as  possible  these  methods  have  been  outlined, 
but  local  conditions  will  often  necessitate  modifications,  and  much 
will  therefore  depend  upon  the  experimenter  or  overseer  of  the 
work. 


CHAPTER  XIX. 
SPRINKLING  WITH  ASPHALTIC  OILS. 

THE  Standard  Oil  Company  is  now  putting  out  an  asphalt 
oil  under  the  brand  of  "Standard  Asphalt  Road  Oil,"  it  is 
a  dust  layer  and  at  the  same  time  a  surface  binder.  The  customary 
plan  is  for  the  municipalities  to  purchase  the  oil  in  tank  cars,  and 
either  sprinkle  it  with  their  own  labor  or  have  some  local  contrac- 
tor do  the  work,  using  an  ordinary  watering  cart.  From  one- 
third  to  one-half  gallon  of  oil  per  square  yard  of  surface  will  pro- 
duce good  results,  the  quantity  used  depending  upon  the  nature 
and  condition  of  the  road. 

The  New  York  State  Engineering  Department  has  used  large 
quantities  of  "Standard  Asphalt  Road  Oil,"  treating  State  roads 
at  Port  Jervis,  Mt.  Upton,  Schuylerville  and  other  points.  County 
roads  have  been  oiled  at  Yonkers,  Rye,  Port  Chester,  Pleasantville, 
White  Plains  and  Hartsdale,  New  York.  Norwalk,  Darien,  Fair- 
field  and  Greenwich,  Connecticut,  and  numerous  other  towns,  and 
the  results  have  been  more  than  gratifying. 

In  many  cases  the  cost  of  oiling  is  less  than  water  sprinkling, 
from  the  fact  that  it  is  only  necessary  to  oil  once  a  season,  whereas 
water  sprinkling  is  a  daily  affair. 

The  Standard  Oil  Company  also  have  an  asphalt  binder, 
known  as  "Standard  Macadam  Asphalt  Binder,"  this  is  a  heavy 
limped  asphalt  used  in  the  construction  of  roads  where  asphaltic 
material  is  used.  Roads  of  this  character  are  sure  to  come  in  the 
East,  California  having  demonstrated  their  durability  and  supe- 
riority over  the  ordinary  macadam  road.  At  Rye,  N.  Y.,  6y2  miles 
of  road  are  being  built  using  the  Asphalt  Binder  in  its  construction. 

The  Standard  Oil  Company,  realizing  the  constantly  increas- 
ing demand  for  asphalt  oil  for  surfacing  roads  has  created  a  dis- 
tinct department  for  supplying  the  same,  not  only  to  municipalities 
but  to  private  individuals  under  the  management  of  Mr.  Henry 
Fisher. 


SPRINKLING   WITH  ASPHALTIC  OILS.  135 

In  this  connection  the  report  of  W.  H.  Dunn,  Superintendent 
of  Parks  tc  the  Board  of  Park  Commissioners,  Kansas  City,  Mo., 
April  20,  1908,  on  "Oiling  Roads,"  is  interesting.  He  stated  that 
undoubtedly  the  most  important  item  of  road  maintenance  for  the 
past  fiscal  year  has  been  the  remarkably  good  results  obtained  from 
oiling. 

Continuing  the  experiment  with  oil  on  rock  roads,  begun  in 
the  summer  of  1906,  the  entire  system  of  driveways  was,  in  1907, 
treated  with  residuum  oil,  now  commonly  called  road  oil.  He 
continued : 

"I  attribute  our  success,  in  a  large  measure,  to  the  fact  that 
we  had  well-built  macadam  roads  to  begin  with,  demonstrating 
that,  when  to  a  perfectly  built  macadam  road  with  a  solid  foun- 
dation and  hard,  smooth  surface,  is  added  the  road  oil  for  a  dust 
preventive  and  protection  to  wearing  surface,  an  inexpensive  treat- 
ment is  given  that  proves  remarkable  in  its  results. 

"Our  roads  to-day,  after  one  year's  trial,  are  in  excellent  con- 
dition, have  gone  through  the  winter  with  less  breaking  up  from 
freezing  and  thawing  than  usual,  and  without  a  particle  of  dust 
after  having  been  once  oiled,  and  without  attention  beyond  the 
ordinary  sweeping. 

"Aside  from  its  value  as  a  dust  preventive,  the  oiled  road  shows 
this  interesting  item  of  reduction  in  maintenance  expense: 

"Sprinkling  driveways  with  water,  for  the  fiscal  year  ending 
April  15,  1907,  cost  $14,011.32,  or  an  average  of  2.4  cents  per 
square  yard.  The  area  of  pavement  to  have  been  sprinkled  in 
1907  (had  not  oil  been  applied)  would  have  cost  $16,207.32. 

"The  total  cost  of  oiling  for  the  year  was  $10,671.44,  a  direct 
saving  in  the  one  item  of  sprinkling  of  $5,538.88,  or  34  per  cent. 

"I  believe  with  an  occasional  light  application  of  oil  through 
this  season  we  will  still  improve  the  wearing  surface  of  our  roads, 
and  eventually  obtain  an  ideal  dustless  pleasure  drive. 

"The  damage  to  wearing  surface  comes  largely  from  attrition 
of  the  grit  or  dust  on  the  roadway.  Oil  compacts  this  grit  or  dust, 
and  immediately  checks  deterioration  from  this  source,  preventing 
any  damaging  effect  from  automobile  travel. 

"The  road  oil  available  for  Kansas  City  is  a  pararHne  base  oil, 
and  becomes  somewhat  slippery  when  applied  on  steep  grades,  but 
is  not  noticeable  on  moderate  grades.  To  overcome  this  objec- 
tion, a  mixture  of  commercial  asphalt  with  residuum  oil  has  been 


136  ASPHALTS.  [CHAP.  xix. 

tried  on  The  Paseo  from  Howard  to  Twenty-fourth  Streets,  with 
excellent  results,  and  further  experiments  will  be  made  this  year 
with  this  material  and  with  an  asphaltic  oil  from  the  Kentucky 
field;  with  this  character  of  oil,  on  grades  exceeding  4  per  cent, 
I  feel  sure  we  will  have  largely  solved  the  dust  problem  in  a 
manner  satisfactory  to  all  concerned. 

"I  submit  the  following  statement  of  oiling  operations  for  1907, 
somewhat  in  detail,  covering  the  oiling  operations  for  the  past 
season  with  a  plan  of  the  unloading  tanks  and  method  of  applica- 
tion. 

"Two  steel  receiving  tanks  of  8,000  gallons  capacity  each 
were  erected  near  our  spur  track  on  the  Belt  Railway,  as  illus- 
trated. The  railroad  tracks  at  this  point  are  at  sufficient  eleva- 
tion to  permit  unloading  tank  cars  by  gravity,  the  receiving  tanks 
also  being  at  such  height  as  to  allow  the  sprinkling  wagons  to  load 
by  gravity.  A  four-inch  pipe  line  connects  the  receiving  tanks  to 
a  short  upright  pipe  in  the  center  of  switch  track,  which  is  con- 
nected to  the  outlet  in  bottom  of  tank  car  by  a  short  piece  of 
adjustable  six-inch  hose,  fastened  with  iron  clamps  around  outside 
of  pipes. 

"A  portable  four-horse  power  boiler  is  erected,  with  ^-inch 
steam  pipe  running  to  each  tank,  which  provides  ample  steam  to 
heat  the  oil  so  it  will  run  freely  and  remain  warm  until  delivered 
on  the  street. 

"This  plant  for  unloading  has  worked  very  efficiently  and  cost, 
erected  and  all  connected  up,  approximately  $750.00. 

"It  was  found  to  be  not  essential  to  heat  the  oil  handled  in  hot 
weather,  after  the  middle  of  June,  and  until  the  middle  of  Sep- 
tember the  oil  ran  freely,  and  no  particular  object  was  gained  by 
heating. 

"Adapting  the  ordinary  street  sprinkling  cart  for  distributing 
oil  on  the  street  was  a  very  simple  matter,  consisting  of  simply 
attaching  (a  tin  trough  six  inches  in  width,  six  inches  in  depth, 
and  long  enough  to  enclose  the  discharge  valves,  perforated  with 
54  -inch  holes  about  one  and  one-half  inches  apart.  The  oil  allowed 
to  come  into  this  trough  through  the  valves  is  then  evenly  dis- 
tributed over  the  road. 

"Applying  oil  to  the  roadway  by  any  process  is  dirty  work 
and  will  inconvenience  the  public  for  a  short  time  while  the  road 
is  being  treated.  To  avoid  accidents,  barricade  the  section  to  be 


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SPRINKLING   WITH  ASPHALTIC  OILS.  137 

treated  (using  one  side  of  the  street  at  a  time),  place  a  sign,  "fresh 
oil,"  on  the  barricade,  which  gives  the  public  fair  notice,  and  then 
go  ahead. 

"The  best  results  were  obtained  when  the  road  was  absolutely 
dry  and  hot. 

"After  sweeping  the  road  as  clean  as  possible  with  a  rotary 
street  broom,  leaving  the  sweepings  along  the  edge  of  the  gutter 
to  prevent  the  oil  running  on  the  cement  work,  the  oil  was  applied 
over  the  entire  surface  and  thoroughly  spread  with  brooms,  after 
which  the  sweepings  from  the  gutter,  with  sufficient  limestone 
screenings  to  form  a  light  dressing,  were  cast  over  the  oiled  sur- 
face and  rolled  down  with  a  road  roller.  The  object  in  using  the 
screenings  is  to  absorb  such  oil  as  does  not  penetrate  into  the  road, 
and  as  soon  as  screenings  are  applied  the  work  is  finished,  and 
no  further  inconvenience  to  the  public  is  encountered. 

TABLE  XI. 
COST  OF  OILING. 

"The  first  application  made  during  May  and  June,  1907,  cost 
as  follows: 

Square  yards  of  pavement  oiled 37  5  A1 5 

Gallons  of  oil  used 120,477 

Total  cost  on  road $5>559-83 

Average  gallons  per  square  yard 0.32  gal. 

Average  cost  per  square  yard I  48-100  cents 

SECOND  APPLICATION. 

Square  yards  pavement  oiled 635,145 

Gallons   oil    used 156,888 

Total  cost  on  road $5,1 1 1.61 

Average  gallons  per  square  yard 0.247 

Average  cost  per  square  yard $0.00805 

TOTAL  OPERATIONS  FOR  THE  YEAR. 

Two  applications  on  375,415  square  yards  cost $8,581.92 

One  application  on  259,730  square  yards  cost 2,089.52 


Total  cost  for  the  year $10,671.44 

Total  number  of  square  yards  oiled   (two  appli- 
cations on  most  of  it) 635,145 

Equivalent  to  one  application  on 1.010,560  sq.  yds. 

At  an  average  cost  per  square  yard  for  oiling  of $0.01055 


138  ASPHALTS.  [CHAP.  xix. 

The  quality  of  oil  used  was  a  residuum  of  20  to  21  gravity, 
Baume. 

Total  amount  of  oil  used,  33  cars,  or  277,365  gallons. 

Average  amount  of  oil  per  square  yard,  0.274  gallon. 

Average  price  paid  for  oil  on  track,  $0.0184  per  gallon  or 
77^2  cents  per  barrel  of  42  gallons. 

"The  above  record  covers  all  cost  of  labor,  supplies  and  oil, 
but  does  not  include  the  cost  of  the  unloading  plant." 


CHAPTER  XX. 

LATEST   VIEWS   OF   CONGRESS   ON   ASPHALT 
SURFACING. 

AT  the  Good  Roads     Convention,   held  at  Atlantic  City,  Sep- 
tember 25  and  26,  1908,  Mr.  James  E.  Owen,  M.  Am.  Soc. 
C.  E.,  of  Montclair,  N.  J.,  in  speaking  on  "What  a  New  Jersey 
Engineer  Should  Do,"  said : 

"First,  we  must  abandon  the  idea  that  it  is  necessary  to  have 
hard  roads;  secondly,  they  must  be  elastic  by  the  interjection  of 
a  suitable  material;  and,  thirdly,  they  must  wear  but  little.  The 
experiments  with  tar  show  that  a  softer  stone  is  better  than  a  hard 
one.  Slag,  limestone,  granite  or  trap  will  be  the  order  of  prefer- 
ence. Appreciating  this,  the  careful  insistence  of  selected  material, 
such  as  trap  or  granite,  which  has  been  our  previous  practice,  need 
not  be  made,  and  the  natural  local  stone  or  gravel  can  be  made 
available. 

"It  seems  hard  for  me,  as  an  engineer  who  has  been  giving 
his  lifework  to  the  construction  of  these  so-called  hard  roads,  to 
take  everything  back;  but  with  the  trend  of  times  and  the  growth 
of  knowledge,  I  am  convinced  that  the  old  practices  will  pass 
away  and  a  new  era  of  road  construction  will  come  to  the  fore. 
This  idea  dawned  on  me  some  years  ago,  and  it  is  now  a  convic- 
tion. 

"Now  another  and  final  point — that  is  maintenance.  With  an 
elastic  medium  in  the  natural  material  the  wear  is  almost  elimi- 
nated; there  is  no  grinding  of  the  surface,  no  dust  and,  conse- 
quently, no  loss.  This  may  seem  rather  visionary,  but  two  instances 
in  my  own  knowledge  confirm  the  statement.  About  eight  years 
ago  an  asphalt  pavement  was  substituted  for  a  Telford.  The  travel 
was  so  great  that  four  to  six  inches  of  stone  was  ground  up  in 
two  years.  Since  the  reconstruction,  no  repairs  have  been  made, 
and  the  pavement  is  in  exactly  the  same  perfect  condition  to-day 
as  when  laid.  Asphalt,  be  it  understood,  is  an  elastic  medium." 


140  ASPHALTS.  [CHAP.  xx. 

He  referred  to  the  very  exhaustive  experiments  made  in  Rhode 
Island  by  Mr.  Arthur  H.  Blanchard,  Assoc.  M.  Am.  Soc.  C.  E.,  and 
quoted  from  his  remarks  as  follows  :* 

"The  conclusions  arrived  at  are  these:  'First,  that  highways 
subjected  to  heavy,  high-speed  motor-car  traffic  should  be  built 
with  a  bituminous  macadam  surface,  constructed  by  the  mixing 
method;  second,  that  existing  macadam  roads  subjected  to  a  similar 
traffic  should  be  reconstructed  as  bituminous  macadam  roads,  using 
the  penetration  method,  or,  if  resurfacing  with  new  road  metal  is 
required,  by  using  the  mixing  method ;  and,  third,  that  the  economi- 
cal and  efficient  treatment  of  macadam  roads  subjected  to  a  mode- 
rate amount  of  motor-car  traffic  is  at  present  a  matter  of  con- 
jecture, requiring  for  elucidation  the  acquisition  of  reliable  detailed 
information  with  reference  to  the  use  of  the  various  palliatives 
now  on  the  market/  ' 

Among  the  materials  upsed  under  his  supervision  was  a  Texas 
asphalt.  It  was  purchased  from  the  Texas  Company,  and  cost, 
delivered  at  South  Ferry,  $21.50  per  ton  of  250  gallons.  The  cost 
of  the  haul  from  the  station  to  the  road,  an  average  distance  of 
2,000  feet,  was  $0.10  per  barrel  of  42  gallons.  Therefore  the  cost 
of  the  asphalt  on  the  road  was  $0.09  per  gallon.  This  asphaltic 
product  is  listed  by  the  Texas  Company  as  Texas  Asphalt,  Grade 
H.  Analyses  yields  practically  no  volatile  matter  to  260°  Fahr. ; 
a  melting  point  of  140°  Fahr.,  and  only  8.8  gr.  per  gallons  in  a 
water  solution. 

Mr.  George  C.  Diehl,  County  Engineer  of  Buffalo,  N.  Y.,  said 
that  asphalt  in  some  form  will  be  the  future  State  road  material 
of  the  country.  Mr.  Diehl  declared  that  asphalt,  mixed  well  with 
stone  and  other  materials,  made  a  durable  and  elastic  road.  The 
author,  speaking  extemporaneously,  said  in  part :  Good  roads  meant 
in  these  days  of  the  automobile,  dustless  roads,  and  that  at  the 
forthcoming  International  Congress  on  Good  Roads,  to  be  held 
in  Paris,  the  vital  question  in  the  convention  would  be  the  most 
approved  method  of  surfacing  the  roads  of  the  world.  To  his 
mind  there  was  no  uncertainty  as  to  the  fact  that  asphalt  in  some 
of  its  various  forms  would  be  the  matrix  of  surface  mixtures; 
the  top  of  the  road  must  be  waterproof,  in  other  words — "dustless" 
— and  that  object  could  alone  be  attttined  by  the  use  of  asphalt. 

*From  a  paper  read  before  the  American  Society  of  Civil  Engineers  at  Den- 
ver, Colo.,  June  25,  1908. 


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ASPHALT    SURFACING.  141 

He  said  that  for  over  thirty  years  he  had  made  the  subject  of 
good  city  streets  his  study,  and  that  during  the  administration  of 
the  late  General  Newton,  previously  Chief  of  the  Engineer  Corps 
of  the  United  States  Army,  he  had  been  called  on  to  act  as  special 
inspector  of  asphalt  pavements,  subsequently  acting  as  general 
inspector  of  pavements  of  the  City  of  New  York,  and  so  super- 
vised, under  the  direction  of  the  late  D.  Lowber  Smith,  C.  E. 
(Fonts  et  Chausses,  Paris),  the  varied  street  pavements  then  in 
vogue.  These  naturally  included  the  Telford-Macadam  pavements 
which  at  that  time — 1886,  1887 — proved  the  best  pavement  for  the 
boulevards  in  the  upper  part  of  the  city.  To-day  these  pavements, 
with  an  adequate  surfacing  of  two  to  three  inches  of  asphalt  con- 
crete, would  afford  a  durable  resiliant  waterproof  and  dustless 
roadway.  As  he  was  not  speaking  in  the  interest  of  any  company 
or  asphalt  industry,  he  called  attention  to  the  fact  that  municipal 
officials  could  purchase  the  materials  and  apply  the  same  them- 
selves. He  said  that  the  methods  of  utilizing  asphalt  with  other 
materials  in  the  most  satisfactory  manner  could  not  yet  be  con- 
sidered as  definitely  settled,  and  that  it  was  engrossing  the  atten- 
tion of  many  able  men.  Mr.  George  C.  Clausen,  of  the  Sicilian 
Asphalt  Paving  Company,  two  years  ago,  had  laid  experimental 
strips  in  Bronx  Park,  New  York,  and  this  year  was  supervising 
tjie  construction  of  a  large  stretch  of  roadway  in  that  park,  using 
the  "Sicilian  asphalto,"  and  guaranteeing  same  for  five  years.  He 
called  the  attention  of  the  convention  to  the  fact  that  many  of  the 
delegates  would,  within  a  few  days,  be  going  over  the  race  course 
laid  out  by  the  Automobile  Club  for  the  race  to  be  held  on  the 
225th  anniversary  of  the  founding  of  their  neighboring  "City  of 
Brotherly  Love,"  and  that  they  would  pass  over  a  section  of  road 
treated  with  "asphalithic"  surface,  laid  at  the  intersection  of  Bel- 
mont  Avenue  and  the  city  line,  by  the  Filbert  Paving  and  Construc- 
tion Company,  of  Philadelphia.  He  said  that  he  had  on  the  previous 
day  called  on  Mr.  J.  L.  Rake,  the  general  agent  of  the  Barber 
Asphalt  Paving  Company,  who  had  informed  him  that  his  com- 
pany was  deeply  interested  in  the  subject  of  dustless  roads,  and 
had  laid  asphalt  concrete  in  a  number  of  cities  and  towns;  their 
expert,  Professor  Clifford  Richardson,  who  had  complete  charge 
of  the  laying  of  the  experimental  roadways,  as  one  of  the  repre- 
sentatives of  the  United  States  government,  and  additionally  as 
the  representatives  of  the  States  of  New  York  and  the  Amer- 


142  ASPHALTS.  [CHAP.  xx. 

ican  Society  of  Civil  Engineers,  had  just  sailed  for  Paris  to 
attend  the  International  Congress,  and  so  could  not  be  present 
at  this  convention.  The  speaker  said  that  he  himself  had  a  num- 
ber of  experimental  pavements  under  way,  and  that  in  view  of 
the  remarks  of  Mr.  Beemer,  the  Deputy  State  Highway  Com- 
missioner of  Pennsylvania,  on  the  scarcity  of  broken  stone  in  his 
State,  he  would  add  that  he  had  arranged  for  an  experimental 
pavement  to  be  laid  with  asphalt  and  slag.  He  had  hoped  to  have 
had  an  oportunity  of  asking  Dr.  Cushman,  while  on  the  platform, 
of  the  latest  results  of  the  United  States  government  investiga- 
tions on  this-  method  of  construction.  He  said  that  contrary  to  the 
condition  of  affairs  in  the  past  century,  this  country  was  not  now 
dependent  on  sources  of  supply  from  Europe,  the  West  Indies 
or  South  America,  and  that  the  United  States  could  now  produce 
all  the  bitumens  necessary  for  the  boundless  calls  the  future  would 
necessitate  for  furnishing  asphalt  concrete.  He  said  that  a  great 
many  of  our  States  could  furnish  liquid  maltha  or  asphalt  which 
could  be  refined  to  any  consistency  required,  enumerating  Cali- 
fornia, Texas,  Indiana,  Kansas,  Kentucky,  Ohio,  Pennsylvania 
and  possibly  New  York.  He  claimed  that  any  oil  with  an  asphal- 
tine  and  petroline  base  could  be  refined  to  yield  a  satisfactory  pav- 
ing material,  but  that  parafine  base  oil  must  be  studiously  avoided. 
In  the  discussion  that  followed  the  delivery  of  the  address,  Mr. 
Beemer  said  he  doubted  whether  Pennsylvania  produced  a  petroline 
base  oil,  and  the  speaker  promised  to  make  definite  investigations 
on  the  question.  A  delegate  objected  that  the  author  had  not 
dwelt  upon  the  subject  of  the  necessary  foundation,  and  the  latter 
replied  that  he  was  addressing  himself  principally  to  engineers  and 
public  officials,  who  realized  fully  that  a  solid  foundation  was  the 
prerequisite  for  any  well-paved  street  or  road.  In  reply  to  the 
question  of  cost  of  the  asphalt  concrete  two-inch  surface,  the 
speaker  stated  that  it  would  mean  an  additional  expense  of  not 
over  twenty  cents  per  square  yard  above  the  cost  of  an  ordinarily 
constructed  macadam  road. 

On  his  way  to  attend  the  First  International  Congress  of  Road 
Builders,  held  in  Paris,  Mr.  Samuel  Hill,  of  Seattle,  Wash.,  who  has 
given  many  years  of  his  life,  and  many  dollars  from  his  purse  to 
foster  the  idea  of  macadamizing  the  roads  of  the  United  States,  and 
particularly  of  his  home  State,  was  accompanied  by  two  other 
delegates,  Mr.  R.  H.  Thompson,  city  engineer,  of  Seattle,  and  Mr. 


DETAIL   OF   SPRINKLER   ATTACHMENT   FOR   OILING. 
\V.  H.  Dunn,  Superintendent  of  Parks,  Kansas  City,  Mo. 


"A  S  P  H  A  LT  S1 


ASPHALT    SURFACING.  143 

Samuel  C.  Lancaster,  Professor  of  Good  Roads  in  the  Washington 
State  University. 

Mr.  Hill,  who  is  president  of  the  Washington  Good  Roads 
Association,  said:  "Many  delegates  from  every  State  in  the  Union 
were  to  attend  the  congress,  Mr.  Parker,  president  of  the  Massa- 
chusetts Highway  Commission,  and  Mr.  Fletcher,  secretary  of  the 
commission,  being  among  the  number. 

"There  is  little  use  of  my  reciting  the  history  of  road  building 
to  you,"  said  Mr.  Hill,  to  a  New  York  Herald  reporter,  "how  it 
began  with  the  Romans,  how  Napolean  carried  the  matter  along 
and  all  that,  but  I  do  want  to  say  that  France  led  the  world  in  road 
building  until  a  few  years  ago,  when  its  highways  began  to  de- 
teriorate, and  that  is  the  primary  reason  for  the  coming  congress. 
In  England  there  came  the  Telford  process  of  road  construction, 
and  the  Macadam,  which,  however,  is  totally  different  from  what 
we  understand  by  that  term  to-day.  But,  on  a  broad  plane,  I 
should  say  that  the  Macadam  process  carries  out  the  theory  of 
building  a  tight  roof  over  a  dry  cellar. 

"I  take  it  that  the  building  of  good  roads  is  the  most  im- 
portant question  that  confronts  the  American  people  to-day.  Every 
man,  woman  and  child  must  use  the  highways  at  some  time, 
whether  afoot,  on  horseback,  in  a  road  wagon  or  in  automobiles. 
The  first  man  to  call  attention  to  the  need  of  good  public  roads 
was  A.  J.  Cassatt,  now  dead,  and  he  was  followed  by  James  H.  Mc- 
Donald, of  Connecticut,  who  is  president  of  the  American  Road 
Makers'  Association.  Understand  at  the  outset,  please,  that  this 
work  of  ours  is  only  for  the  betterment  of  the  country  and  that  no 
man  who  has  given  time  and  thought  to  the  project  has  done  other 
than  to  put  out  money  from  his  own  pocket,  with  no  hope  of  ever 
getting  it  back,  much  less  of  viewing  it  as  an  investment. 

"Of  the  men  who  are  to  accompany  me  as  delegates  to  the 
congress  from  Washington  Mr.  Thompson  is  one  of  the  ablest  of 
municipal  engineers,  and  it  was  he  who  recognized  the  fact  that,  in 
the  building  of  asphaltum  roads  any  material  having  more  than 
three  per  cent  of  fixed  carbon  would  be  injurious.  His  ideas  were 
put  into  operation,  each  consignment  of  asphaltum  was  tested. 

"Mr.  Lancaster  has  the  chair  in  the  department  of  Good  Roads 
in  the  Washington  State  University,  the  first  institution  to  establish 
such  a  course.  It  is  a  popular  one,  too.  It  had  one  hundred  and 
twenty-five  students  in  1907,  and  this  year  it  began  with  no  less  than 


144  ASPHALTS.  [CHAP.  xx. 

two  hundred  men  in  the  class.  We  think  in  Washington  that  we 
have  the  best  laws  in  the  world  as  far  as  the  making  of  good  roads 
is  concerned,  for  they  have  been  compiled  with  the  greatest  care. 
Mr.  Lancaster  is  carrying  on  a  great  educational  work.  We  have 
organized  bureaus  for  the  dissemination  of  information  about  the 
State  roads,  and  have  opened  a  schoolhouse  campaign  where  lectures 
are  held  and  photographs  and  lantern  slides  showing  the  highways 
throughout  the  State  and  those  in  foreign  countries,  which  I  have 
gathered  in  my  many  journeys,  are  shown  to  those  who  attend. 

"When  I  became  interested  actively  in  the  subject,  about  four 
years  ago,  I  made  up  my  mind  that  I  would  ascertain  just  what  it 
cost  one  of  our  farmers  to  haul  along  the  roads  for  one  mile  garden 
truck  and  other  material  weighing  one  ton.  For  on  the  farmer 
principally  falls  the  burden  of  our  bad  roads.  I  learned  that  be- 
cause of  the  poor  roads  the  United  States  lost,  with  the  setting  of 
the  sun  every  day,  nearly  $3,000,000  which  might  be  saved  were 
the  roads  in  proper  condition.  Just  think  of  that!  And  yet  not  a 
cent  has  come  from  the  federal  administration  for  the  betterment 
of  these  roads.  Some  States,  as  Washington,  and  a  few  others, 
have  appropriations,  but  not  in  proportion  to  the  calling  necessity. 
Then  we  began  to  get  busy  in  our  State  of  Washington. 

"We  put  the  convicts  at  work  and  we  found  the  process  was 
a  great  success.  Each  convict  netted  to  the  State  $4.03  for  each 
day  of  work,  which  amounted  to  something.  And  not  one  convict 
turned  out  to  this  task  tried  to  escape.  North  Carolina  led  in  this 
system  of  convict  labor,  and  that  was  fifteen  years  ago,  and  now  it 
has  eighteen  hundred  miles  of  macadamized  roads  built  by  convict 
labor,  and  only  two  per  cent,  of  the  men  employed  in  this  way  tried 
to  escape.  In  Washington  the  majority  of  our  roads  are  constructed 
over  mountains  and  at  a  maximum  grade  of  five  per  cent.  This  con- 
vict labor  did  not  interfere  with  union  labor,  either,  for  with  the  con- 
struction of  the  roads  there  was  more  work  for  the  union  men  in 
other  branches  of  the  task. 

"Let  me  tell  you  of  our  method  in  Washington.  We  build  our 
roads  usually  about  one  hundred  feet  wide.  First  we  have  in  the 
middle  a  strip  about  sixteen  feet  wide.  On  the  bottom  we  take  from 
the  screen  cubes  of  rock  about  two  and  a  half  inches.  This  rock 
is  put  down  wet,  and  a  ten-ton  steam  roller  goes  over  it  from  the 
sides,  to  make  it  cement  and  rise  high  in  the  middle.  Then  comes 
rock  one-half  the  size  of  the  other,  and  then  the  rock  three-quarter 


"ASPHALTS" 


ASPHALT    SURFACING.  145 

inch  cubes.  Over  this  is  poured  asphalt,  melted  to  about  one  hun- 
dred and  eighty  to  two  hundred  degrees  Fahrenheit,  and  over  all 
this  is  thrown  the  fine  pebbles.  Then  the  steamroller  gets  to  work 
again.  Parallel  to  this  strip  we  make  a  path  of  light  material, 
designed  for  horses  and  vehicles ;  alongside  that  comes  a  bridle  path, 
for  equestrians  only,  and  then  comes  another  strip  of  grassy  lawn, 
with  flowers  and  trees.  We  maintain  that  strip  in  all  strictness. 

"In  contrast  with  this  let  me  tell  you  that  in  the  Bois  de  Bou- 
logne, in  Paris,  a  road  was  put  down  last  year,  and  that  now  it  is 
full  of  holes  and  worthless,  and  that  the  automobiles  which  passed 
along  it  raised  such  clouds  of  dust  that  the  grass  disappeared  and 
tour  trees  which  for  years  had  been  the  pride  of  Parisians  were 
killed.  The  Chief  Road  Engineer  of  Paris  has  told  this  to  us  in  a 
report  and  he  has  asked  the  visitors  to  the  congress  to  view  this 
worthless  road. 


CHAPTER  XXL 
MUNICIPAL  ASPHALT  PLANTS. 

THERE  are  today  in  America  Municipal  plants  operated  in  the 
following  cities :  Winnipeg,  Man. ;  Columbus,  O. ;  Dayton, 
O. ;  Toledo,  O. ;  New  Orleans,  La. ;  Toronto,  Ontario ;  Detroit, 
Mich. ;  Allegheny,  Pa. ;  Omaha,  Neb. ;  and  Seattle,  Wash.,  has  lately 
contracted  for  the  erection  of  a  plant..  In  the  October,  1908,  issue 
of  the  "Municipal  Engineering"  the  following  interesting  data  was 
given  by  that  magazine,  which  for  so  many  years  has  given  the 
closest  attention  to  matters  pertaining  to  the  asphalt  industries 

It  is  said  that  the  number  of  municipal  repair  plants  is  increas- 
ing gradually  and  a  few  of  them  have  now  been  in  use  long  enough 
to  give  some  idea  of  the  cost  of  operating  them  so  that  at  least  a 
preliminary  comparison  can  be  made  with  the  contract  system  still 
in  use  in  most  cities.  Such  plants  as  those  at  Columbus,  O.,  and 
Indianapolis,  Ind.,  have  not  been  in  operation  long  enough  to  give 
more  than  a  daily  force  and  material  account  and  the  actual  effect  of 
idle  time,  accidents,  depreciation,  repairs,  etc.,  cannot  be  given  ex- 
actly. The  figures  from  them  will  be  given  more  fully  when  more 
reliable  statements  can  be  made. 

Under  the  contract  system  in  some  cities  the  price  bid  is  per 
square  yard  of  pavement  replaced.  The  prices  vary  greatly,  being 
$1.65  in  Minneapolis  and  St.  Paul;  $1.50  in  Utica,  N.  Y. ;  about 
$1.35  in  Indianapolis  in  1906;  $1.35  to  $1.50  in  Columbus,  O. ; 
$1.75  in  1897  in  Rochester,  N.  Y.,  reducing  gradually  each  year 
to  $1.27  in  recent  years;  $1.23  to  74  cents  in  Buffalo,  N.  Y. ;  89 
cents  in  Toronto,  Ont. ;  66  cents  in  Indianapolis  in  1907.  The  last 
named  contract  was  the  cause  of  much  scandal  on  account  of  an 
alleged  attempt  to  make  up  for  the  low  price  by  over-measurements 
of  areas  of  work  done. 

Other  contracts  are  per  cubic  foot  of  material  placed,  measure- 
ments being  taken  at  the  plant  as  the  wagons  are  loaded.  Under 
the  contract  system  Brooklyn,  N.  Y.,  paid  in  1905  67  cents  per 
cubic  foot  for  wearing  surface  and  25  cents  per  cubic  foot  for 


SPIKING   UP   OLD    ROADWAY. 


SAME   ROADWAY  ONE   DAY  LATER. 
The    Kelly-Springfield    Road    Roller    used. 


37 


"A  S  P  H  A  L  T  S' 


MUNICIPAL    ASPHALT    PLANTS.  147 

binder.  Washington,  D.  C,  paid  49  and  25  cents,  respectively.  A 
compression  of  one-sixth  in  laying  makes  the  cost  of  the  asphalt 
wearing  surface  in  place  in  the  pavement  78  cents  per  cubic  foot  in 
Brooklyn  and  57  cents  in  Washington. 

The  cost  of  laying  asphalt  in  repairs  by  the  Brooklyn  municipal 
asphalt  repair  plant,  which  went  into  operation  in  June,  1907,  has 
been  85.19  cents  per  cubic  foot  of  wearing  surface  and  74.46  cents 
per  cubic  foot  of  binder.  These  figures  include  materials,  labor, 
transportation,  supervision,  fixed  charges,  maintenance  and  opera- 
tion of  plant  machinery  and  tools.  If  the  thickness  of  the  wearing 
surface  is  assumed  at  2  inches,  as  in  New  Orleans,  the  cost  of  wear- 
ing surface  per  square  yard  becomes  $1.28. 

It  is  not  easy  to  reduce  the  reported  costs  of  running  the  New 
Orleans  municipal  asphalt  repair  plant  to  the  same  basis  as  the  fig- 
ures given  above  on  account  of  numerous  differences  in  conditions ; 
for  example,  absence  of  binder  and  greater  thickness  of  wearing 
surface.  The  plant  was  used  for  laying  new  asphalt  pavements  as 
well  as  for  repairing  old  pavements.  Material  and  labor  costs  were 
kept  separately,  special  charges  against  the  asphalt  plant  as  a  whole 
were  divided  equally  between  the  new  and  repair  work  and  general 
charges  against  the  paving  and  repair  department  were  divided 
among  the  three  sections,  new,  repair  and  miscellaneous  work,  35 
per  cent,  going  to  the  repair  section.  The  "naphtha  coat"  was  laid 
under  about  two-thirds  the  asphalt  wearing  surface  deposited,  and 
new  concrete  was  put  under  about  one-eighth  of  it.  Deducting  the 
cost  of  the  concrete  at  87  cents  a  square  yard,  the  figure 
derived  from  the  data  regarding  the  work,  the  remainder  will 
give  the  combined  cost  of  naphtha  coat  and  wearing  surface 
for  all  the  repairs  made.  This  cost  averages  $1.03  a  square  yard, 
and  does  not  include  depreciation  and  interest  on  cost  of  plant, 
which  may  amount  to  15  cents  a  square  yard,  making  a  total  of 
$1.1 8.  It  is  quite  possible  that  this  figure  is  too  high,  for  new  pave- 
ments, deducting  cost  of  grading  and  concrete  foundations,  seem 
to  have  cost  only  63  cents  a  square  yard  for  the  naphtha  coat  and 
asphalt  wearing  surface,  as  compared  with  $1.03  above.  Repair 
work  is  more  expensive  than  new  work,  but  this  difference  of  40 
cents  seems  to  be  excessive  and  may  be  due  to  errors  in  either  or 
both  items  made  in  the  rather  complicated  distribution  of  costs. 

The  first  season  of  the  Columbus,  O.,  repair  plant  has  not  yet 
ended,  but  the  operators  of  the  plant  have  been  obliged  to  fix  a 


148  ASPHALTS.  [CHAP.  xxi. 

price  for  work  done  for  other  persons  than  the  city  and  have  set 
$1.25  a  square  yard  as  a  price  for  such  work,  which,  including  all 
general  and  special  items,  plant  and  fixed  charges,  as  well  as  main- 
tenance and  operation,  will  cover  the  actual  cost  with  as  little  margin 
as  is  safe  in  the  absence  of  full  data. 

Various  reports  from  the  Detroit,  Mich.,  plant  have  shown 
83.6  cents  per  square  yard  cost  of  materials  and  labor  and  $1.05 
including  all  items  of  cost. 

In  Allegheny,  Pa.,  one  report  shows  75  cents  a  square  yard  as 
the  cost  of  asphalt  repairs  for  material  and  labor. 

An  unofficial  report  from  Dayton,  O.,  indicates  a  cost  of  57 
cents  a  square  yard,  which  probably  includes  only  materials  and 
labor. 

The  average  cost  in  the  Montreal  municipal  asphalt  plant  is 
$1.22  a  square  yard,  including  all  work  in  connection  with  the  re- 
pair. 

The  Winnipeg  municipal  asphalt  plant  keeps  detailed  records 
of  the  work  done.  Records  of  laying  new  pavements  are  at 
hand.  Deducting  from  the  total  cost  for  new  pavements  the  cost 
of  grading,  sand  foundation,  concrete  and  binder,  and  40  per  cent, 
of  the  general  charges,  leaves  the  cost  of  laying  the  wearing  surface 
87  cents  per  square  yard.  This  is  doubtless  somewhat  less  than  the 
cost  of  laying  the  same  area  of  repair  work. 

Allowing  for  the  difference  in  conditions  in  these  various  cities 
it  is  fair  to  fix  on  about  85  to  90  cents  per  square  yard  as  the  aver- 
age cost  of  laying  repair  work  for  materials  and  labor,  and  say 
$1.15  to  $1.25,  including  all  charges  in  municipal  plants.  Cost  of 
the  various  materials  and  of  labor  and  the  weather  conditions  pro- 
duce variations  each  way  from  these  averages. 

Cities  letting  their  asphalt  repairs  by  contract  have  considered 
prices  fair  when  they  range  from  $1.25  to  $1.50,  according  to  local- 
ity. The  difference  indicates  the  cash  saving  to  the  street  repair 
departments. 

Several  cities  have  installed  plants  for  doing  their  own  asphalt 
repair  work,  not  so  much  because  they  expected  a  reduction  in  the 
cost  of  the  work,  as  for  the  purpose  of  securing  complete  control 
of  the  kinds  and  qualities  of  materials  to  be  used  and  time  of  making 
repairs.  In  these  respects  the  cities  have  found  the  results  very  sat- 
isfactory, enough  so  to  warrant  some  increase  in  cost.  However, 


38 


"AS  PH  A  LT  S' 


MUNICIPAL    ASPHALT    PLANTS. 


149 


at  the  above  figures  will  show,  a  reduction  in  cost  has  also  resulted 
in  nearly  every  case. 

Contractors  for  asphalt  work  express  themselves  frequently 
as  being  greatly  pleased  with  the  results  from  the  municipal  asphalt 
repair  plants.  They  are  usually  able  to  induce  the  municipal  plant 
to  do  repair  work  and  small  jobs  at  a  reasonable  price,  which,  while 
greater  than  the  cost  to  them  if  their  plant  is  running,  saves  them 
much  expense  if  the  plant  must  be  started  up  for  a  small  amount 
of  work  or  particularly  if  a  plant  must  be  moved  in  from  some 
other  city.  The  city's  street  repair  department  is  more  than  satisfied 
because  it  has  complete  control  of  the  materials  and  workmanship 
and  can  thus  insure  good  work  done  at  the  right  time. 


CHAPTER  XXII. 
ASPHALT  WATERPROOFING. 

THE  extent  to  which  asphalt  enters  into  waterproofing  construc- 
tion can  be  imagined  when  it  is  seen  that  the  Sicilian  Asphalt 
Paving  Co.  in  the  New  York.  Rapid  Transit  Subway,  the  Penna. 
R.  R.  Terminals  and  Tunnels  in  New  York  and  New  Jersey,  the 
N.  Y.  Central  and  H.  R.  R.  R.  Terminals  and  Improvements  in 
New  York  and  the  Sixth  Ave.  Subway  of  the  Hudson  R.  Tunnel 
system  laid  over  20,000,000  square  feet  of  waterproofing. 

The  author  has  taken  advantage  of  the  courtesy  of  Mr.  A.  M. 
Tipper,  of  the  Texas  Co.,  and  gives  in  full  a  paper*  prepared  by  him 
•dealing  comprehensively  with  the  subject  of  waterproofing.  Mr. 
Tipper  says  that  "the  last  ten  years  have  witnessed  a  rapid  increase 
in  the  field  of  cement  usefulness.  The  formative  character  of  con- 
crete and  the  ease  with  which  it  is  adapted  to  a  continually  enlarg- 
ing number  of  structures  have  brought  the  concrete  engineer  in 
immediate  touch  with  problems  connected  therewith  which  for  years 
were  largely — if  not  entirely — ignored. 

"The  experiences  of  concrete  engineers  and  contractors  in 
their  progress  with  the  application  of  concrete  to  structure  building 
of  all  kinds  have  shown  them  that  in  the  practical  field  work,  under 
the  conditions  oftentimes  inevitable,  with  the  natural  imperfections 
which  attend  any  work  conducted  in  the  mass,  have  proved  to  them 
that  for  many  purposes  to  which  concrete  is  at  present  applied  it 
is  necessary  to  protect  the  concrete  structure  and  to  prevent  percola- 
tion through  it.  These  experiences  have  also  shown  the  architect 
and  engineer  that  the  field  of  cement  usefulness  would  be  greatly 
enlarged  if  there  is  supplied  a  perfect  method  of  protection  and 
waterproofing. 

"For  this  reason  the  waterproofing  problem  is  at  the  present 
time  attracting  the  attention  of  all  architects  and  engineers ;  and  on 
account  of  its  importance  in  the  increasing  application  of  cement  of 


°A  paper  read  by  Mr.  A.  M.  Tipper  before  the  Cement  Products' 
Exhibition  Co.,  December,  1907. 


39 


'ASPHALT 


ASPHALT    WATERPROOFING.  151 

great  interest  to  the  cement  manufacturers,  while  to  the  cement 
users  the  importance  of  the  problem  cannot  be  overestimated.  The 
action  of  railroad  companies,  large  construction  companies  and 
others  in  their  investigation  of  waterproofing  is  evidence  of  the 
interest  displayed  in  this  subject  and  the  necessity  of  adoption  of 
waterproofing  for  the  protection  of  the  concrete  structure.  It  may 
be  said,  in  fact,  that  this  protection  is  the  necessary  requirement 
for  the  consideration  of  concrete  work  as  permanent.  Climate  con- 
ditions, atmospheric  impurities,  etc.,  may  aid  disintegration.  Many 
propositions  have  been  brought  forward  with  the  object  of  water- 
proofing in  all  kinds  of  ways  by  different  methods,  frequently  with 
the  result  of  disgusting  the  engineer  with  futile  attempts  at  solving 
his  problem  or  with  dismay  at  the  cost. 

"A  large  amount  of  the  trouble  experienced  in  the  satisfactory 
waterproofing  of  concrete,  and  the  consequent  costly  and  incon- 
venient experiments,  have  been  the  direct  result  of  a  want  of  knowl- 
edge of  the  application  suited  to  the  local  conditions  which  obtain  in 
the  structure  to  which  the  waterproofing  is  to  be  applied,  a  want 
of  consideration  of  the  requirements  of  waterproofing  or  a  total 
disregard  to  the  relative  cost  which  the  protection  should  bear. 

"Out  of  this  mass  of  experiments  and  gradual  formation  of 
satisfactory  waterproofing  propositions  has  come  the  belief  that  the 
most  satisfactory  method  of  waterproofing  concrete  structures 
under  all  irdonary  conditions,  the  most  inexpensive  and  the  most 
extensive  in  its  possible  applications  is  by  the  application  of  a 
bituminous  coating  on  the  surface  of  the  concrete.  It  raises  no 
question  as  to  possible  deleterious  effects  upon  the  concrete  as  do 
the  compounds  which  enter  the  concrete  mix,  these  being  the  sub- 
ject of  considerable  disagreement  among  engineering  chemists  as 
to  their  ultimate  effect  upon  the  concrete  mass. 

"The  application  of  the  bituminous  coat  upon  the  concrete  sur- 
face is  a  very  simple,  inexpensive  proposition,  readily  handled  with 
unskilled  labor  after  a  little  training  and  satisfactory  in  its  results. 

"Much  poor  waterproofing  has  been  done  in  the  past  with  so- 
called  bituminous  products  of  all  kinds,  and  much  distrust  has  fallen 
upon  the  method  by  reason  thereof,  either  from  a  want  of  knowl- 
edge of  the  material  or  a  want  of  consideration  of  the  effect  of  its 
use.  For  a  considerable  period  coal  tar  products  were  used  in  this 
connection  and  at  the  present  time  are  still  occasionally  used.  The 
properties  and  composition  of  coal  tar  products  make  them  thor- 


152  ASPHALTS.  [CHAP.  xxn. 

oughly  unsatisfactory  as  a  waterproofing.  They  neither  hold  their 
ductility  nor  pliability,  becoming  brittle  at  comparatively  high  tem- 
peratures and  soft  at  comparatively  low  temperatures,  quickly  losing 
the  small  bonding  and  elastic  qualities  they  possess,  and  in  a  short 
time  becoming  absolutely  worthless. 

"The  first  requirement  of  waterproofing  covering  for  concrete 
is  that  it  shall  be  impervious  to  water,  and  here  the  necessity  of 
pure  asphaltic  bitumen  for  the  purpose  is  thoroughly  illustrated. 
Samples  of  two  different  kinds  of  asphalt  taken  and  held  in  water 
for  over  one  year  at  a  pressure  of  150  pounds  to  the  square  inch 
showed  that  one  of  these  samples  had  absorbed  no  moisture,  while 
the  other  had  increased  more  than  129  per  cent,  in  weight,  owing 
to  the  absorption  of  water.  Both  of  these  asphalts  claimed  to  be 
pure  material  and  were  guaranteed  as  such,  yet  evidently  the  one 
product  was  waterproof,  while  the  other,  without  some  readjusting, 
was  decidedly  porous.  Pure  asphaltic  bitumen,  that  is,  with  over 
99  per  cent,  pure  bitumen  in  its  composition,  should  show  no  ab- 
sorption of  moisture  at  all,  presenting  an  absolutely  impermeable 
surface.  A  further  important  requirement  in  bituminous  water- 
proofing is  its  range  of  ductility,  and  here  it  is  necessary  to  state 
that  the  fact  that  the  product  presented  for  waterproofing  is  pure 
bitumen  does  not  necessarily  include  a  high  range  of  ductility  or  a 
particularly  brittle  point.  The  proportions  of  the  petrolenes  and 
asphaltenes  composing  the  bitumen  may  vary,  in  which  case  the 
brittle  point  and  range  of  ductility  may  vary.  It  is  therefore  essen- 
tial for  the  protection  of  the  user  that  the  range  of  ductility  be 
asked  for. 

"It  is  necessary  that  the  bitumen  be  of  sufficiently  high  melting 
point  to  insure  its  remaining  solid  under  any  of  the  conditions  of  its 
work,  and  it  is  just  as  imperative  that  it  should  remain  pliable 
under  any  of  the  conditions.  This  makes  it  evident  that  the  water- 
proofer  should  be  conversant  with  the  local  conditions  of  the  work 
his  material  will  be  against  on  any  particular  proposition. 

"In  one  test  asked  for  the  waterprofing  was  spread  one-fourth 
inch  thick  on  burlap,  placed  against  a  strong  grating  arranged  in 
a  testing  machine  provided  with  a  pump  for  pumping  ice  water,  in 
which  was  floating  crushed  ice.  The  specifications  called  for  the 
waterproofing  material  withstanding  a  pressure  of  10  pounds  with- 
out the  coating  becoming  brittle  and  cracking  or  passing  water  and 
that  it  should  not  melt  below  225  degrees  Fahrenheit.  All  samples 


p 

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SI 


£  S 

> 


'ASPHALT 


ASPHALT    WATERPROOFING.  153 

but  one  broke  at  seven  pounds.  The  successful  sample  stood  10 
pounds  pressure,  which  was  then  continued  for  twenty-four  hours, 
at  the  end  of  which  time  it  showed  no  defect.  It  was  then  deter- 
mined to  conduct  a  breakdown  test,  which  resulted  in  the  sample 
withstanding  a  pressure  of  300  pounds,  when  the  packing  blew,  but 
the  waterproofing  still  remained  intact. 

"The  waterproofing  bitumen  must  therefore  be  pure  and  have  a 
long  range  of  ductility,  and  as  an  important  corollary  the  water- 
proofing manufacturer  must  be  able  to  suit  his  material  and  applica- 
tion to  local  circumstances  and  conditions. 

"It  is  very  evident  that  to  provide  a  waterproof  floor  for  a 
warehouse  where  there  is  heavy  trucking,  etc.,  over  it,  is  a  different 
proposition  from  waterproofing  a  bridge  floor,  and  it  is  equally  as 
evident  that  the  method  of  application  in  the  case  of  the  railroad 
bridge,  where  the  headroom  between  floor  and  rail  is  small  is  a 
totally  different  proposition  from  the  bridge,  where  the  headroom  is 
14  to  20  feet. 

"Briefly,  the  ordinary  method  of  waterproofing  by  using  a 
bituminous  coating  and  the  one  used  under  a  number  of  conditions 
is  by  the  application  of  a  priming  coat  of  paint,  which  has  light 
enough  body  to  enter  the  pores  of  the  concrete  and  form  an  anchor- 
age for  the  heavier  bituminous  coat.  On  top  of  this  is  mopped  a 
hot  coat  of  pure  bitumen.  This  coat  is  of  varying  thickness,  accord- 
ing to  the  work,  from  one-sixteenth  of  an  inch  on  a  concrete  roof  to 
one- fourth  or  one-half  inch  for  bridge  floors  and  deep  foundations. 
Where  the  coating  is  exposed  to  the  effect  of  cutting  or  chipping 
some  reinforcement  through  the  coat  or  some  hard  mastic  mix  is 
necessary.  For  vertical  structures  where  the  cutting  effect  is  not 
accompanied  by  heavy  load  the  reinforcement  of  the  coating  by  the 
application  of  a  single  ply  burlap  is  sufficient.  Where,  however, 
the  waterprofing  is  horizontal  and  there  is  a  cutting  load  above,  it  is 
often  advisable  to  use  a  mastic  mix. 

"The  following  specifications  for  the  asphalt  will  insure  good 
material  for  this  work: 

"Asphalt  shall  be  used  which  is  of  the  best  grade,  free  from 
coal  tar  or  any  of  its  products,  and  which  will  not  volatilize  more 
than  one-half  of  I  per  cent,  under  a  temperature  of  300  degrees 
Fahrenheit  for  ten  hours. 

"For  metallic  structures  exposed  to  the  direct  rays  of  the  sun, 
the  asphalt  should  not  flow  under  212  degrees  Fahrenheit  and 


154  ASPHALTS.  [CHAP.  xxn. 

should  not  brittle  at  15  degrees  below  freezing  Fahrenheit  when 
spread  thin  on  glass. 

"For  structures  underground,  such  as  masonry  arches,  abut- 
ments, retaining  walls,  foundation  walls  of  buildings,  subways,  etc., 
a  flow  point  of  185  degrees  Fahrenheit  and  a  brittle  point  of  zero 
Fahrenheit  will  be  required. 

"The  asphalt  covering  must  not  perceptibly  indent,  when  at  a 
temperature  of  130  degrees  Fahrenheit,  under  a  load  at  the  rate 
of  15  pounds  per  square  inch,  and  it  must  remain  ductile  at  a  tem- 
perature of  15  degrees  below  freezing  Fahrenheit  on  metal  struc- 
tures, and  at  zero  Fahrenheit  on.  masonry  structures  under  ground. 

"In  the  application  of  coatings  requiring  a  hard  surface  the 
finishing  coat  should  be  sprinkled  with  a  layer  of  hot  washed  roofing 
gravel  torpedo  sand  or  slag  to  provide  a  hard  surface.  If  this  hard- 
surfaced  waterproofing  is  required  of  considerable  thickness,  the 
asphaltic  concrete  of  asphalt  mastic  and  grit  is  the  best  method  of 
waterproofing. 

"Asphalt  is  undoubtedly  the  oldest  waterproofing  known  and 
was  used  centuries  before  the  Christian  era  began.  It  has  proved 
itself  a  thoroughly  satisfactory  coating,  taking  care  of  the  expan- 
sion and  contraction,  and  providing  a  pliable  and  ductile  water- 
proofing, sealing  up  the  pores  in  the  concrete,  covering  hair  cracks 
and  checks,  retaining  its  qualities  for  many  years  without  deteriora- 
tion. 

"Its  insulating  qualities  increase  its  value  in  an  age  when  con- 
crete and  steel  structures  are  being  continually  used  in  places  where 
the  mtal  may  be  subjected  to  electrolitic  action." 

"CALLENDRITE" — (Callender's  Pure  Trinidad  Lake  Bitumen 
Sheeting)  is  extensively  used  on 

WATERWORKS — For  lining  open  and  covered  storage  and  serv- 
ice reservoirs,  filter  beds,  valve  towers,  aqueducts,  &c. 

Old  leaking  reservoirs  or  filter  beds  can  be  made  absolutely 
watertight  by  its  use. 

ON  ROADS — For  covering  bridges,  viaducts  and  arches,  lining 
subways ;  also  for  girder  seatings. 

ON  SEWERAGE  WORKS — For  lining  settling  and  filtering  tanks, 
culverts  and  conduits,  sewers,  &c. 

ON  GAS  WORKS — For  lining  gas  holder  tanks,  &c. 

IN  MINING  AND  COLLIERY  WORKS — For  lining  pit  ponds,  tanks, 
storage  and  condensing  reservoirs,  &c. 


41 


'A  S  P  H  ALTS' 


A  SPHA  L  T    IV  A  TERPROOFING. 


155 


IN  ELECTRICITY  WORKS — For  lining  cooling  ponds,  trans- 
former chambers,  cable  subways,  dynamo  bed  foundations,  &c. 

IN  COLD  STORAGE  CONSTRUCTION — For  lining  chambers  for 
insulating  purposes,  &c. 

The  advantages  of  using  "Callendrite"  for  making  watertight 
the  earthwork  embankments  of  open  storage  and  service  reservoirs 
will  be  apparent  to  the  engineer,  both  from  an  economic  and  a  struc- 
tural point  of  view. 


The  sketch  A,  which  is  a  section  of  an  ordinary  earthwork 
embankment  with  a  clay  puddle  core,  shows  that  the  water  will 
reach  the  face  of  the  puddle  before  it  meets  with  resistance;  so 
that,  in  spite  of  the  existence  of  the  inner  bank  ( I ) ,  the  only 
effective  resistance  to  the  pressure  of  the  water  is  afforded  by  out- 
side bank  (2)  Should  the  puddle  get  damaged,  either  by  settlement 
or  by  the  depredation  of  rats  or  other  vermin,  the  efficiency  of  the 
reservoir  is  destroyed.  The  arrow  on  the  sketch  shows  the  direction 
of  the  pressure  of  the  water. 

If  the  same  reservoir  were  constructed  with  "Callendrite"  as 
shown  in  Sketch  B,  it  will  be  seen  that,  whereas  in  the  former  case 


SKETCH    B 


only  one-half  of  the  embankment  offers  effectual  resistance  to  the 
thrust  of  the  water,  in  Sketch  B  the  whole  of  the  embankment  is 
brought  into  action.  In  addition  to  this,  the  direction  of  the  thrust, 
as  shown  by  the  arrow,  is  such  as  to  render  the  structure  more 
stable,  as  it  now  has  less  tendency  to  overthrow  the  embankment 


156 


ASPHALTS. 


[CHAP.  xxn. 


or  to  make  it  slide,  and  at  the  same  time  tends  to  make  the  embank- 
ment more  homogeneous  and  to  bind  it  closer  to  the  ground  at  its 
base.  Therefore,  when  Callender's  Sheeting  is  employed,  it  is  evi- 
dent that  the  section  of  the  embankment  can  be  considerably  modi- 
fied, and  a  large  reduction  obtained  in  materials  and  cost.  The 
saving  in  materials  is  especialy  important  in  situations  where  the 
amount  of  excavation  is  small  and  the  expense  of  procuring  suitable 


material  for  constructing  the  embankment  consequently  forms  an 
important  factor  in  the  total  cost. 

Where  "Callendrite"  is  used,  it  is  only  necessary  to  line  the 
inner  slopes  of  the  embankments  and  the  floor  of  the  reservoir  with 
a  thin  layer  of  concrete,  so  as  to  form  an  even  surface  for  the  sheet- 
ing, and  then  to  cover  the  latter  with  3  inches  of  concrete  as  a  pro- 
tection from  mechanical  damage  The  thin  layer  of  concrete  cover- 
ing the  sheeting  which  lines  the  inner  slope  of  the  embankment  is 
prevented  from  slipping  by  the  construction  of  a  concrete  toe  at  the 
foot  of  the  slope,  as  shown  in  Sketch  B,  which  at  the  same  time 
prevents  any  tendency  of  the  inner  section  of  the  bank  to  slip  or 
spread.  In  short,  the  use  of  'Callendrite"  not  only  renders  storage 
and  service  reservoirs  absolutely  watertight,  but  secures  perfect 
solidity  and  great  economy  in  their  construction. 


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"A  S  P  H  AL  T  S' 


ASPHALT    WATERPROOFING.  157 

In  the  construction  of  covered  service  reservoirs  "Callendrite" 
is  very  serviceable,  as  its  employment  as  a  lining  entirely  dispenses 
with  the  necessity  of  costly  outside  trenches  filled  with  clay  puddle. 
As  will  be  seen  by  the  accompanying  sketches,  the  main  walls  can 
be  built  in  concrete,  the  sheeting  being  applied  to  the  inner  face  and 
supported  by  an  inner  lining  of  4.^2 -in.  brickwork  or  6-in.  of  fine 
concrete.  The  bitumen  sheeting  covering  the  floor  of  the  reservoir, 
which  is  continuous  with  the  sheeting  lining  the  walls,  is  protected 
by  3  inches  of  fine  concrete,  by  a  course  of  brick  on  edge,  or  by 
paving  stones,  according  to  the  requirements  of  the  case 

Realizing  that  felt  did  not  render  a  sufficiently  strong  fabric 
for  waterproofing,  Mr.  H.  R.  Wardell,  of  the  Barber  Asphalt  Pav- 
ing Co.,  on  a  visit  to  Germany  obtained  the  idea  of  what  he  con- 
sidered a  possible  improvement  on  Callendrite  and  his  company  are 
manufacturing  the  Positive  Seal  Fabric,  which  is  a  saturated  and 
coated  burlap.  This  material  is  used  in  connection  with  Positive 
Seal  Liquid  or  Solid  Cement,  as  the  case  demands,  in  layers  or  plies. 
It  is  strong  and  resilient.  It  will  give  and  twist,  bulge,  expand  or 
contract,  but  never  break,  and  so  long  as  it  does  not  break  it  will 
positively  seal  against  water.  This  fabric  has  a  much  greater 
tensile  strength  than  any  felt  made.  For  waterproofing,  roofing 
or  dampcoursing  specify  the  construction  the  same  as  when  using 
felt,  except  one-half  the  number  of  plies  to  get  the  same  results. 
It  is  supplied  in  rolls  of  300  square  feet. 


CHAPTER  XXIII. 
ASPHALTS    IN    ROOFING. 

OVER  thirty  years  ago  the  author  had  a  year's  experience  with 
the  Warrens,  who,  at  that  time,  had  just  started  the  use  of 
asphalt  in  place  of  coal  tar  -residuum  for  asphalt  roofs,  and  with 
interest  he  now  recalls  his  visits,  in  company  of  the  late  Samuel  M. 
Warren,  to  architects'  offices  when  they  carried  with  them  a  segar 
box  containing  a  little  alcohol  cooking  machine  with  which  they 
gave  practical  demonstrations  of  how  the  volatile  oil  of  coal  tar 
pitch  evaporated  and  left  dust,  while  the  asphalt  retained  its  elas- 
ticity and  body  under  similar  heat.  The  Warrens  manufactured 
their  asphalt  felts  at  Sixth  street,  Long  Island  City,  and  on  the 
south  side  of  Seventh  street  the  author,  in  conjunction  with  the  late 
Edwin  H.  Wootton,  built  in  1892  the  New  York  Mastic  Works  for 
the  Compagnie  Generale  des  Asphaltes  de  France,  the  sites  of  which 
are  now  owned  by  the  Val  de  Travers  Asphalte  Paving  Co.,  of 
London,  and  the  Cyrus  Warren  Estate. 

Mr.  Samuel  M.  Warren  in  1845  was  engaged  in  the  business 
of  laying  pine  tar  roofs,  and  coal  tars  at  that  time  were  the  waste 
products  of  the  gas  works.  He  conceived  the  idea  of  using  coal 
tars  to  mix  with  pine  tar  pitches,  and  almost  immediately  thereafter 
used  coal  tar  for  saturing  dry  felt  in  making  roofing  paper.  The 
first  experiments  and  use  occurred  in  Cincinnati.  Mr.  Warren  was 
then  a  young  man,  and  the  opportunities  for  the  development  seemed 
so  great  that  his  brothers,  John  Warren,  Cyrus  M.  Warren,  Her- 
bert M.  Warren  and  E.  Burgess  Warren,  successfully  and  almost 
immediately  enteeed  with  their  brother  upon  contracting  systemati- 
cally for  the  largest  supplies  of  tars  in  the  United  States.  The 
various  brothers  controlled  at  one  time  the  tars  produced  in  Cin- 
cinnati, St.  Louis,  New  York  City,  Philadelphia,  Baltimore  and 
Washington,  D.  C. 

John  Warren,  who  located  in  Buffalo,  N.  Y.,  is  entitled  to  the 
credit  for  first  distilling  coal  tar  and  making  coal  tar  pitch;  and 
its  immediate  substitution  for  pine  tar  spread  over  the  United 


- 
•o  O 


££   O 


4:', 


'A  S  P  H  A  LT  S' 


ASPHALTS    IN    ROOFING.  159 

States.  Hendricks'  Architectural  Engineering  and  Mechanical  Di- 
rectory of  the  United  States  gives  names  and  addresses  of  over 
seven  thousand  concerns  now  actively  engaged  in  the  laying  of  this 
kind  of  roofing.  The  business  was  almost  immediately  so  prosper- 
ous that  out  of  the  revenues  Mesrs.  Cyrus  M.  Warren  and  Samuel 
M.  Warren  took  courses  in  Harvard  College,  the  latter  afterward 
being  professor  of  organic  chemistry  in  the  Massachusetts  Institute 
of  Technology  and  the  author  of  that  part  of  Dana's  work  on  hydro- 
carbons which  appeared  in  Dana's  work  on  mineralogy. 

When  petroleum  came  on  the  market  the  Warrens  were  among 
the  first  distillers  in  the  United  States,  and  Mr.  Cyrus  M.  Warren 
became  recognized  as  the  best  authority  on  the  use  of  bituminous 
materials,  and  invented  the  process  of  fractional  distillation  of 
petroleum  and  coal  tar  oils,  which  process  has  given  to  the  world 
all  the  numerous  by-products.  The  commercial  growth  of  the  busi- 
ness up  to  1870  was  phenomenal,  and  all  of  the  best  energies  were 
necessarily  applied  to  the  commercial  development  rather  than  to 
scientific  investigation.  In  1870  reverses  came  and  found  the  War- 
rens with  large  contracts  for  tar,  with  a  falling  market  and  increased 
competition  in  the  price  of  tar  and  manufactured  goods. 

At  this  time  competition  made  necessary  the  development  of 
something  new  and  better,  and  Cyrus  M.  Warren  invented  the 
asphalt  roofing  which  has  so  long  been  manufactured  by  the  Warren 
Chemical  and  Manufacturing  Company,  and  they  became  the  first 
large  importers  and  refiners  of  asphalt  in  this  country. 

The  early  failure  of  the  coal  tar  bitumens  in  concrete  construc- 
tion, owing  to  the  price  at  which  they  were  laid,  furnished  no  in- 
centive for  development,  and  a  general  view  prevailed  that  concretes 
in  which  coal  tar  bitumens  were  used  were  deficient  in  every  respect 
and  should  be  excluded  from  all  standard  specifications.  A  monop- 
oly in  the  control  of  asphalt  made  it  commercially  profitable  to  decry 
even  the  best  coal  tar  bitumens  and  to  extend  the  use  of  asphalts. 
Yet  it  seems  to  be  a  fact  that  the  early  asphalt  pavements  were  as 
great  a  failure  as  the  early  coal  tar  pavements. 

In  recent  years  the  Warrens  have  played  a  prominent  part  in 
the  development  of  the  asphalt  pavements  of  the  country.  Mr.  E. 
Burgess  Warren  was  one  of  the  organizers  and  one  of  the  largest 
stockholders  of  the  Barber  Asphalt  Paving  Company,  and  for  many 
years  its  vice-president.  Cyrus  M.  Warren  was  the  organizer  and 
the  president  of  the  Warren-Scharf  Asphalt  Paving  Company,  and 


160  ASPHALTS.  [CHAP.  xxm. 

) 

in  the  management  of  this  company  and  of  the  Warren  Chemical 
and  Manufacturing  Company  and  other  allied  interests  he  was  aided 
by  his  brothers,  sons  and  nephews,  and  there  have  been  engaged  in 
the  business  over  twenty-two  Warrens,  but  today  no  member  of  the 
family  is  interested  in  the  roofing  business. 

/One  of  the  pioneers  of  the  prepared  roofing  business  is  the 
Stowell  Manufacturing  Company,  who,  in  the  manufacture,  unite 
the  skill  and  experience  developed  by  years  of  constant  and  careful 
attention  devoted  to  the  manufacture  of  asphalt  roofings,  exclu- 
sively, with  the  highest  quality  of  raw  materials  available,  without 
regard  to  their  cost. 

The  best  quality  of  fibrous  pure  wool  felt  is  saturated  with 
genuine  Trinidad  Lake  Asphalt  and  heavily  coated  with  the  same 
material  of  a  stiffer  consistency  and  into  which  is  firmly  imbedded 
a  dense  surfacing  of  crushed  granite,  felspar,  ground  asbestos  fibre, 
cork,  gravel,  sand  or  ground  mica  nad  slate. 

They  produce  ten  varieties  of  surfaced  roofings  as  well  as  sev- 
eral thicknesses  of  saturated  roofing  felts  of  one,  two  and  three  ply. 

Among  these  varieties  of  surfaced  roofings  are  found  those 
suitable  for  any  class  or  style  of  buildings  as  roofing,  sheathing  or 
exterior  surfacings. 

These  products  are  made  from  natural  Trinidad  Asphalt  ex- 
clusively, and  no  coal  tar  or  coal  tar  products  whatsoever  are  used. 
As  a  result  these  felts  do  not  dry  out  or  become  stiff  or  brittle.  On 
the  contrary  they  are  flexible  and  tough,  yielding  readily,  and  with- 
out injury,  to  contraction  and  expansion. 

This  line  of  surfaced  goods  affords  successful  resistance  against 
the  action  of  weather,  acids  and  gaseous  vapors,  as  well  as  against 
ignition  from  flying  firebrands,  or  burning  cinders.  They  remain  in 
good  condition  in  any  climate  on  flat  or  pitched  roof  or  if  applied  to 
the  perpendicular  sides  of  buildings. 

Asphalts  are  used  for  "prepared"  or  "ready"  roofings  by  a 
number  of  companies  and  under  an  endless  variety  of  brands,  fol- 
lowing the  name  of  "Ruberoid,"  manufactured  by  the  Standard 
Paint  Company,  a  prolific  list  of  roofings  has  been  put  on  the  market 
ending  with  "oid."  The  "Paroid"  is  a  well  known  brand  in  which 
asphalt  is  partially  used,  and  the  "Flintkote,"  manufactured  at 
Rutherford,  N.  J.,  by  the  Flintkote  Manufacturing  Company,  is 
made  with  pure  asphalts.  The  Trinidad  Asphalt  Manufacturing 
Company,  of  St.  Louis,  Mo.,  among  its  manufactures  includes  Rub- 


SINGER  BUILDING. 

Hetzel's  Rubber  Roof  Cement  used  in  this  building;  supplied  by  J.  G. 
Hetzel  Estate,  Newark,  N:  J. 


ASPHALTS    IN    ROOFING.  161 

bero.  Among  other  users  of  asphalt  for  their  roofings  are  the 
Barber  Asphalt  Paving  Company,  who  make  the  "Genasco"  brands ; 
the  Lincoln  Waterproofing  Company,  of  Bound  Brook,  N.  J. ;  the 
National  Roofing  Company,  of  Tonawanda,  N.  Y.,  and  several 
Western  concerns.  Malthoid,  originally  manufactured  in  Califor- 
nia, is  now  also  made  in  New  Jersey  by  the  Standard  Paint  Com- 
pany. The  Johns-Manville  Company  also  use  large  quantities  of 
asphalt  in  connection  with  their  roofing  materials.  The  efforts  made 
by  the  Warrens  to  extend  the  use  of  asphalt  for  graveled  surfaced 
roofs  has  not  been  sustained  of  late,  but  in  cases  of  high-class  work 
such  as  the  New  York  Custom  House  and  generally  for  United 
States  Government  work  genuine  asphalt  is  called  for  under  a  vitri- 
fied brick  tile  surface. 

The  rock  asphalt  roofs  so  extensively  used  in  Europe  seem  to 
have  gone  out  of  vogue  in  the  United  States,  and  in  these  days  of 
roof  gardens,  it  is,  of  course,  necessary  to  have  a  roof  not  dented 
by  chairs,  &c.  It  is  probable  that  reduction  in  cost  of  the  native 
asphalts  will  cause  a  return  to  its  use  for  ordinary  graveled  or  slag 
roofings,  as  the  cost  will  now  compare  favorably  with  what  have 
lately  been  considered  cheaper  pitches.  An  ordinary  slag  surface 
specification  would  read  about  as  follows : 

STANDARD  TILE  ROOFING. 
SPECIFICATION. 

The  grade  of  the  roof,  which  should  be  at  least  one-fourth  inch 
to  one  foot,  should  be  formed  by  the  mason,  and  the  surface  of  the 
concrete  finished  smooth  and  hard  by  him  before  the  roofer  begins. 
The  roofer  should  coat  the  surface  of  the  concrete  with  hot  asphalt 
cement  in  quantity  sufficient  to  completely  cover  the  same;  over 
which  lay  five  thicknesses  of  best  quality  asphalt  roofing  felt.  The 
felt  to  be  laid  shingle  fashion — beginning  at  the  lowest  point,  with 
all  laps  stuck  for  at  least  two-thirds  of  their  width  with  hot  asphalt. 
Metal  flashings  shall  extend  out  on  this  felt  for  four  inches,  and  the 
roofer  shall  cover  them  with  two  felt  strips  securely  cemented  in 
place  with  hot  asphalt.  The  entire  exposed  surface  of  the  felt  to  be 
then  coated  wit  hhot  pitch,  over  which  lay  6x9x1 -inch  vitrified  roof- 
ing tiles. 

Tiles  to  be  laid  in  one  inch  of  cement  mortar — composed  of  one 
part  of  Portland  cement  (or  equal)  to  three  parts  sand.  Tiles  to 


162  ASPHALTS.  [CHAP.  xxm. 

be  laid  true  to  grade,  joints  broken,  and  the  roof  finished  by  grout- 
ing joints  with  liquid  grout  composed  of  one  part  each  of  sand  and 
cement. 

ASPHALT  SLAG  ROOFING. 
SPECIFICATION. 

On  fireproof  construction  the  surface  of  the  concrete  should 
first  be  coated  with  hot  asphalt,  in  quantity  sufficient  to  completely 
cover  the  same,  then  proceed  as  over  wooden  construction. 

On  wooden  construction  the  roof  boards  should  be  smooth, 
solid  and  laid  closely  together.  Commence  at  eaves  or  gutter 
and  lay  full  four  thicknesses  of  best  asphalt  roofing  felt,  the 
felt  to  be  laid  shingle  fashion,  with  one-fourth  the  width  of  each  lap 
exposed.  Securely  nail  on  back  of  each  sheet  with  nails  and  tin 
caps.  All  laps  to  be  thoroughly  stuck  for  at  least  two-thirds  of  their 
width  with  natural  Asphalt  Roofing  Cement,  applied  hot.  The  en- 
tire surface  of  the  felt  then  to  be  coated  with  the  same  material, 
into  which  shall  be  bedded  clean,  dry  roofing  slag. 

Ten  gallons  of  asphalt  and  three  hundred  pounds  of  slag  to  be 
used  on  each  one  hundred  square  feet  of  surface. 


TOWER  FOR  SE'AII-PORTABLE  ASPHALT  PLANT. 


45 


"A  S  P  H  A  LT  S' 


CHAPTER  XXIV. 
ASPHALT  FOR  MANUFACTURE. 

THE  uses  to  which  asphalt  may  be  applied  as  an  ingredient 
in  manufactures  are  multitudinous,  and  the  author  cannot 
pretend  to  enumerate  them.  Photography,  ink  manufacture  and 
endless  industries  call  for  the  use  of  this  material  to  a  greater  or  less 
extent. 

Mr.  John  A.  Yates,  a  prominent  civil  engineer,  who  was  in 
charge  of  the  building  of  the  forts  at  Fort  Wadsworth  during  the 
Spanish- American  war,  said  that  it  is  a  recognized  fact  that  asphalt 
is  such  a  thorough  waterproof  and  insulating  material  that  the 
Insulatine  Company  of  New  York  are  using  it  in  considerable  quan- 
tities in  the  manufacture  of  their  insulating  and  electrical  cements. 

Mr.  David  Szende,  Director  of  the  Hungarian  Asphalt  Com- 
pany, Budapest,  while  on  a  visit  to  New  York  about  five  years  ago, 
gave  the  author  some  information  on  the  making  of  varnish  from 
Derna  asphalt  which  may  be  interesting.  The  Derna  asphalt  is  a 
high-class  bitumen  extracted  from  bituminous  sandstone  very 
similar  to  that  found  in  the  Indian  Reservation. 

Take  a  quantity  of  the  Derna  mineral,  and  after  breaking  it  into 
pieces  as  large  a  fist,  put  it  into  an  open  iron  or  copper  boiler, 
which  should  be  previously  cleaned,  especially  from  any  greasy  or 
fatty  substances.  A  good  fire  will  soon  melt  the  material,  which 
will  become  quite  liquid  by  being  stirred  occasionally.  It  is  advan- 
tageous when  once  liquid  to  let  it  boil  for  2  or  3  hours  without 
stirring,  merely  skimming  it  from  time  to  time.  In  this  warm  state 
it  should  be  put  into  a  clean  vessel  and  an  equal  weight  of  turpen- 
tine gradually  added  whilst  stirring  the  material.  Nothing  further 
is  required,  the  varnish  is  now  ready  for  use.  If  it  is  wished  to 
make  a  thicker  kind  of  varnish,  which  will  cover  better,  then  add 
only  45  parts  of  turpentine  to  55  of  Derna.  As  long  as  the  varnish 
is  hot  it  remains  in  a  thin  state  and  only  obtains  the  necessary  con- 
sistency when  cold.  If,  through  being  kept  too  long,  the  varnish 
becomes  too  thick  it  can  be  thinned  by  adding,  in  a  cold  state,  a 


164  ASPHALTS.  [CHAP.  xxiv. 

little  turpentine.  The  quality  of  the  varnish  depends  solely  on  the 
class  of  turpentine  used.  It  is  observed  further  that  when  using  a 
very  hot  fire  the  mineral  at  times  ignites  without  coming  into  direct 
contact  with  the  flames.  Care  should,  therefore,  be  taken,  and  appli- 
ances held  ready,  to  close  as  nearly  as  possible  hermetically  the 
boiler  in  case  of  the  material  taking  fire.  The  Hungarian  Company 
use  a  wrought  iron  cover  and  sand  to  fill  any  crevices.  It  does  not 
matter  if  sand  falls  into  the  material  as  it  will  sink  to  the  bottom 
of  the  boiler  and  can  be  removed.  During  the  operation  of  boiling 
the  material,  and  mixing  it  with  turpentine,  the  boiler  and  vessels 
used  must  not  be  closed. 

An  important  industry  is  that  of  cork  boards  and  insulating 
materials  used  extensively  for  breweries,  cold  storage  warehouses 
and  packing  houses. 

Star  Cork  Boards  are  made  by  the  United  Cork  Companies. 
They  are  manufactured  from  best  grade,  screened,  granulated,  nat- 
ural cork,  every  granule  of  which  is  coated  with  an  odorless,  water- 
proof compound,  and  compressed  into  board  form.  During  the 
entire  process  the  cork  is  not  subjected  to  extreme  heat  or  great 
pressure  as  is  the  case  with  othed  materials  of  a  similar  character. 
Excessive  pressure  destroys  the  cellular  structure,  and  extreme  heat 
destroys  the  life  and  vitality  of  the  cork  and  its  insulating  prop- 
erties. 

Although  cork  is  practically  free  from  capillarity,  they  go  a 
little  further  by  using  a  special  asphalt  binder,  which  gives  "Star" 
Cork  Board  even  more  insulating  value  than  pure  cork,  inasmuch 
as  the  material  they  use  is  absolutely  waterproof  and  impervious  to 
moisture,  preventing  deterioration  and  decay.  In  addition  it  is 
highly  aseptic  and  will  not  decompose  nor  cause  the  cork  to  disin- 
tegrate. Gums,  glues  or  cements  have  no  such  capacity  to  resist 
moisture,  and  cork  board  made  up  with  them  will  not  be  perma- 
nently satisfactory. 

"Star"  Cork  Boards  are  made  12  inches  wide  by  36  inches  long 
in  any  thickness  from  i  inch  upward.  They  are  squared  to  accu- 
rate dimensions  thus  making  possible  tightfitting  work  with  no  open 
joints.  The  boards  can  easily  be  sawed  same  as  lumber  to  fit  uneven 
o  rirregular  surfaces,  thus  further  insuring  continuous  and  com- 
plete insulation.  On  account  of  the  compact  form  of  the  boards 
they  possess  superior  structural  strength  and  are  adaptable  to  any 
construction  of  building. 


46 


"ASPHALTS' 


ASPHALTS    FOR    MANUFACTURE.  165 

The  electric  companies  use  the  material.  Fuse  works  are  among 
its  purchasers,  and  varnish  manufacturers  all  use  it  in  some  grade 
or  another,  varying  from  the  high-class  Egyptian  to  the  cheapest 
American  grades. 

One  of  the  most  important  uses  of  asphalt  not  previously  re- 
ferred to  is  that  of  the  filling  of  joints  of  granite  and  brick  pave- 
ments. For  streets  with  steep  grades  granite  block  with  asphalt 
fillers  is  the  best  construction,  and  such  pavement  is  generally  to  be 
found  on  the  piers  and  heavy  traffic  streets  of  European  cities.  Its 
advantages  for  this  purpose  may  be  briefly  enumerated  as  follows : 

1.  It  provides  for  expansion. 

2.  It  provides  for  contraction. 

3.  It  is  absolutely  waterproof. 

4.  It  is  permanent. 

5.  Cracks  are  avoided. 

6.  It  leaves  sufficient  joints  for  foothold. 

7.  It  is  easy  to  use  correctly. 

8.  The  pavement  can  be  cut  without  destroying  the  blocks. 
Any  of  the  first-class  bitumens  will  serve  this  purpose,  but  some 

care  must  be  used  in  discriminating  against  too  highly  oxidized 
material  and  so-called  asphalts  produced  by  "secret  process." 


CHAPTER  XXV. 
ASPHALT  MACHINERY. 

MACHINERY  naturally  enters  largely  into  the  asphalt  industry, 
and  much  expense  has  been  incurred  in  perfecting  various 
improvements  in  working  plants  and  refineries.  A  somewhat  re- 
cent improvement  is  a  sand  dryer,  which  has  been  the  means  of 
quite  a  large  saving  in  the  cost  of  paving  mixtures  for  sheet  asphalt 
pavements.  This  was  evolved  from  suggestions  from  several 
asphalt  experts  by  the  engineer  of  the  Coatesville  Boiler  Works. 
No  less  than  four  of  these  dryers  are  now  in  use  at  the  plant  of  the 
Cranford  Paving  Company,  Brooklyn.  The  Filbert  Paving  Con- 
struction Company  and  Carey  &  Reed,  of  Philadelphia,  also  speak 
highly  of  the  advantages  gained  by  the  use  of  this  machine. 

These  dryers  have  been  developed  during  the  past  few  years  in 
the  actual  work  of  drying  sand  and  similar  materials. 

While  in  a  general  way  they  are  the  cylinder  dryer  in  general 
use,  they  have  a  number  of  new  features  which  are  vitally 'import- 
ant to  the  satisfactory  working  of  these  machines,  as  they  are  built 
upon  the  broad  principal  of  bringing  the  hottest  products  of  com- 
bustion next  to  the  dryest  material,  which  is  the  reverse  from  the 
ordinary  sand  dryer.  This  is  not  only  theoretically  correct,  but  it 
has  been  found  most  excellent  in  actual  practice.  The  drying  is 
more  rapidly  and  thoroughly  done  and  there  is  practically  no  dust 
nor  fine  material  driven  from  the  dryer,  owing  to  the  fact  that  dust 
or  fine  aterial  picked  up  by  the  blast  is  caught  by  the  fresh  ma- 
terial as  it  enters  the  dryer. 

Then  again  these  dryers  are  made  for  hard  and  constant  use. 
Every  portion  of  the  material  is  what  has  been  found  in  actual  prac- 
tice to  be  best  for  this  character  of  work.  At  all  points  where  the 
mechanism  is  affected  by  expansion  and  contraction  due  to  the 
rapid  heating  and  cooling  of  the  apparatus,  provision  is  made  to 
prevent  damage  to  any  part  of  the  structure.  As  a  prominent  user 
has  suggested,  after  four  years  of  constant  use,  it  is  a  plain,  prac- 


"A  S  P  H  ALT  S' 


ASPHALT    MACHINERY.  167 

tical,  substantial  machine  and  as  nearly  fool  proof  as  a  machine  can 
be  made. 

The  shells  are  made  perfectly  cylindrical.  The  tires  upon 
which  they  rest  are  steel  forging  turned  all  over  to  insure  perfect 
balance,  and  these  tires  are  secured  to  the  shll  by  springs.  The 
same  arrangement  secures  the  driving  mechanism  to  the  shell.  The 
interior  construction  is  forged  steel,  so  arranged  as  to  be  practically 
indestructible,  and  the  material  is  dropped  through  the  hot  flame 
and  gas  from  the  furnace  in  a  continuous  shower,  thus  subjecting 
every  part  of  it  to  the  heat  in  such  manner  as  to  dry  it  evenly  and 
rapidly. 

The  attachments  for  the  dryer,  including  blower,  blast  gates, 
&c.,  are  so  arranged  that  the  operator  has  absolute  control  of  the 
temperature  at  all  times. 

An  asphalt  plant  with  a  capacity  of  1,500  square  yards  per  9- 
hour  day  has  been  built  for  the  city  of  Toronto,  Ont,  by  the  Warren 
Asphalt  Paving  Company,  of  Boston,  at  a  contract  price  of  $28,575. 
Its  purpose  is  to  enable  the  city  to  carry  out  all  repair  work 
promptly  and  probably  lay  a  few  small  pavements  each  year.  Com- 
plaints have  been  frequent  in  the  past  that  openings  in  asphalt  pave- 
enmts  were  not  promptly  repaired,  and  it  is  expected  that  no  unrea- 
sonable delay  will  arise  hereafter  in  executing  such  work.  The 
buildings  have  steel  frames,  galvanized  roofs  and  sides,  and  rein- 
forced concrete  floors.  The  machinery  was  recently  described  in  a 
report  by  City  Engineer  C.  H.  Rust  as  follows : 

There  are  two  self-contained  rotary  driers,  manufactured  by 
Warren  Asphalt  Paving  Company,  the  revolving  cylinders  being 
40  inches  in  diameter  and  19  feet  6  inches  long.  Draft  is  supplied 
by  a  5O-inch  exhaust  fan,  which  discharges  into  a  Cyclone  dust  col- 
lector. The  driers  are  fed  by  two  chain  elevators,  and  the  hot  sand 
or  stone  is  discharged  into  an  enclosed  elevator  and  conveyed  to 
steel  storage  bins  holding  10  cubic  yards  each,  situated  on  the  sec- 
ond floor,  the  stone  bin  being  fitted  with  a  rotary  screen.  There  is 
also  a  storage  bin  for  limestone  dust  provided  on  the  second  floor, 
having  a  capacity  of  4  cubic  yards  and  fed  by  a  dust  elevator.  The 
hot  material  and  the  dust  are  drawn  by  gravity  into  their  respective 
weighing  boxes  which  discharge  into  the  mixer;  the  mixer  has  a 
capacity  of  1,100  pounds  of  topping  mixture. 

The  asphalt  cement  is  prepared  in  three  enclosed  melting  tanks 
provided  with  mechanical  agitation  and  having  a  capacity  of  2,000 


168  ASPHALTS.  [CHAP.  xxv. 

imp.  gals.  each.  The  asphalt  cement  is  elevated  by  air  pressure  to 
the  asphalt  weighing  bucket,  running  on  an  overhead  trolley  to  the 
mixer.  The  storage  tank  for  flux  has  a  capacity  of  10,000  imp. 
gals.  The  flux  is  blown  from  it  to  the  weighing  tank  on  the  first 
floor  and  drawn  by  gravity  into  the  kettles. 

The  asphalt  barrels  are  hoisted  to  the  charging  floor  by  a  barrel 
elevator.  Power  to  the  main  portion  of  the  plant  is  supplied  by  a 
ioxi2-in.  engine,  manufactured  by  the  Erie  Engine  Works,  and  to 
the  agitating  tanks  and  barrel  elevator  by  a  5x5~in.  engine,  manu- 
factured by  the  Sturtevant  Blower  Works.  Compressed  air  foi 
forcing  the  asphalt  cement  out  of  the  tanks  and  other  purposes  is 
furnished  by  a  6x8xi2-in.  Knowles  direct-acting  air  compressor. 
Steam  is  supplied  to  these  engines  by  a  6o-horsepower  Star  water 
tube  boiler.  Street  and  plant  tools,  including  8-ton  and  5-ton  steam 
asphalt  rollers,  five  wagons,  hand  rollers,  pitch  kettles,  &c.,  and 
twelve  Wilkinson  asphalt  dump  wagons,  complete  the  equipment. 


CHAPTER  XXVI. 

ROCK    ASPHALT    MAINTENANCE.* 

IN  the  discussion  two  years  ago  the  author  stated  that  Nelson  P. 
Lewis,  M.  Am.  Soc.  C.  E.,  Chief  Engineer  of  the  Board  of 
Estimate  and  Apportionment  of  the  City  of  New  York,  had  con- 
sidered that  rock-asphalt  pavements  were  probably  the  best  that 
had  been  laid.  George  W.  Tillson,  M.  Soc.  C.  E.,  objected 
to  it  because  he  considered  the  maintenance  charges  on  it  exces- 
sive. The  speaker,  therefore,  begs  to  state  that  rock-asphalt  corn- 
prime  has  been  laid  in  the  United  States  in  New  York,  Brooklyn, 
Long  Island  City,  and  Rochester,  in  New  York  State;  Elizabeth 
and  Perth  Amboy,  in  New  Jersey;  Boston,  Mass.;  New  Haven, 
Conn. ;  Philadelphia,  Pa. ;  and  New  Orleans,  La. 

The  first  comprime  work  was  laid  in  Union  Square,  New  York, 
in  1872.  In  August,  1897,  H2th  Street,  from  Fifth  to  Lenox 
Avenues  was  laid,  and  the  city  records  show  that  in  1912  the  cost 
of  repairs  on  this  street  was  only  6  cents  per  sq.  yd.;  and  loist 
Street,  from  Lexington  Avenue  to  Park  Avenue,  paved  in  July, 
1896,  with  Mons  and  Sicilian  rock,  bears  no  cost  for  repairs  from 
1910  to  1913.  Such  durability  seems  to  be  unparalleled  in  the  his- 
tory of  street  construction.  On  Dyckman  Street,  from  Kingsbridge 
Road  to  the  tracks  of  the  New  York  Central  and  Hudson  River 
Railroad,  8,000  sq.  yd.  of  Seyssel  and  Sicilian  rock  asphalt  were 
laid  in  the  late  fall  of  1897,  and  the  cost  of  maintenance  for  the 
4  years,  1910  to  1913,  inclusive,  was  3  cents  per  sq.  yd.,  or  less 
than  i  cent  per  sq.  yd.  per  year.  In  1901,  between  Park  and  Lex- 
ington Avenues,  35th  and  36th  Streets  were  paved  with  Seyssel 
and  Sicilian  rock  asphalt ;  on  36th  Street  no  repairs  were  necessary 
for  the  4  years,  1910-13.  In  the  same  year  I3th  Street,  from 
Second  to  Third  Avenues,  was  paved  with  Sicilian  and  Mons  rock 
on  an  old  stone  foundation,  and  is  charged  with  14  cents  per  sq.  yd. 
for  4  years'  maintenance.  In  1897,  io6th  Street,  from  Broadway 


*Read  before  the  Am.  Soc.  C.  E.,  January  24th,  1914. 


170  ASPHALTS. 

to  Riverside  Drive,  was  paved  with  Sicilian  and  Mons  rock,  and 
shows  cost  for  repairs  of  17  cents  per  sq.  yd.  for  4  years,  a  trifle 
more  than  4  cents  per  year. 

To  come  to  more  recent  times,  it  was  decided  in  1912  by  the 
Department  of  Highways,  under  the  advice  of  E.  P.  Goodrich, 
M.  Am.  Soc.  C.  E.,  Consulting  Engineer  to  the  President  of  the 
Borough  of  Manhattan,  to  lay  a  series  of  test  pavements  on  Second 
Avenue,  from  Houston  to  23d  Streets.  Rock  asphalt  comprime, 
or  natural  Sicilian  rock  powder  was  laid  between  iQth  and 
2ist  Streets,  and  on  inspection,  in  January,  1914,  these 
blocks  were  found  to  be  in  fair  condition,  the  chief  imperfection 
being  in  the  work  adjoining  the  car  tracks.  This  is  not  to  be 
wondered  at,  as  all  rock  asphalt  experts,  such  as  Malo,  Delano, 
Walsh  of  Amsterdam,  Bassett  of  London,  and  almost  all  engineers 
in  Europe  have  decided  that  granite  or  other  blocks  should  be  laid 
longitudinally  beside  car  tracks.  The  speaker  recommends  scoria 
blocks.  The  most  noticeable  of  all  the  experimental  pavements  on 
Second  Avenue  is  that  of  rock  asphalt  compressed  blocks,  between 
Qth  and  nth  Streets.  These  blocks  were  manufactured  with 
an  ordinary  German  brick  machine,  and  did  not  receive  the  perfect 
compression  obtained  by  the  Val  de  T ravers  Asphalte  Paving  Com- 
pany in  their  works  at  Marseilles,  Seyssel,  and  Cairo,  Egypt,  and 
elsewhere.  However,  the  rock  being  pure  crude  asphalt  powder 
before  being  pressed,  simply  spread  under  heavy  traffic,  and  became 
virtually  a  monolithic  sheet  of  rock  asphalt,  and  it  affords  to-day 
as  perfect  a  specimen  of  rock  asphalt  pavement  as  can  be  seen 
in  any  country. 

Mr.  Delano,  on  the  occasion  of  his  visit  to  New  York  in  No- 
vember, 1913,  stated  that  the  City  of  Paris  had  recently  signed 
contracts  for  replacing  wood  blocks,  stone  sets,  and  macadam  with 
700,000  sq.  m.  of  rock  asphalt  pavement,  to  be  laid  during  the  next 
5  years.  Attention  is  also  called  to  the  fact  that,  some  years  ago, 
Thomas  Street,  from  Broadway  to  Church  Street,  and  Trimble 
Place,  from  Thomas  to  Duane  Streets,  both  private  streets  owned 
by  fifty  associates,  were  paved  with  Neuchatel  Rock  Asphalte  Paves 
and  coated  with  an  asphalt  rubber  surface  coat,  only  ^  in.  thick, 
which  has  stood  the  heavy  traffic  of  those  busy  thoroughfares  for 
several  years. 

The  speaker  can  prove  that  rock  asphalt  is  the  most  valuable 
pavement  in  the  United  States.  This  is  stated  especially  because 


DRIVEWAYS     LAID     WITH     EUROPEAN     ROCK     ASPHALTIC 
PAVES     BY     L.     L.     WRIGHT. 


BASEMENT      FLOOR      OF      ST.      JOSEPH'S      CHURCH, 

PACIFIC    AVENUE,    BROOKLYN,    N.    Y. 
Laid    with    European    Rock    Asphalt    Mastic    by    L.    L.    Wright. 


'A  S   P  H    A   L   T   S1 


ROCK    ASPHALT    MAINTENANCE.  171 

so  many  engineers  doubt  that  any  European  rock  asphalt,  such 
as  laid  in  London,  Paris,  and  Berlin,  has  ever  been  laid  in  the  United 
States.  The  speaker  is  sorry  that,  owing  to  the  short  time  allotted 
to  him,  he  will  have  the  opportunity  to  say  but  little  about  its 
history  in  America. 

The  reason  this  subject  of  the  practicability  of  the  use  of  Euro- 
pean Rock  Asphalte  is  so  much  more  important  than  when  the  dis- 
cussion before  the  Society  was  held  in  1912,  is  that  the  tariff  on 
asphalt  has  been  removed,  and  Rock  Asphalte  powder  can  now  be 
purchased  at  a  cost  of  $3  per  ton  less  than  in  1913,  making  a  differ- 
ence of  25  cents  per  sq.  yd.  in  the  cost  of  the  surface.  Municipal 
plants  can  be  supplied  with  the  material,  all  ready  for  heating  and 
compressing  on  the  street,  and  no  additional  outlay  for  machinery  is 
necessary.  Both  the  Borough  of  Manhattan,  which  is  now  com- 
pleting its  new  municipal  asphalt  plant,  and  the  City  of  Philadelphia 
are  considering  the  advisability  of  doing  their  own  repairs  to  rock 
asphalt  streets. 

*In  January,  in  the  discussion  on  Col.  Howard's  paper  on  "Eu- 
ropean Rock  Asphalts,"  the  writer  said:  "I  am  sure  all  have  been 
much  interested  in  the  paper  delivered  by  Colonel  Howard.  It  is 
a  noticeable  fact  that  army  officers  have  been  so  much  interested 
in  asphalt  pavements.  Two  chiefs  of  the  U.  S.  Engineering  Corps 
devoted  much  time  to  the  subject.  General  H.  G.  Wright  advised 
the  paving  of  Pennsylvania  Avenue  with  Neuchatel  rock  asphalt; 
General  John  Newton,  on  whose  civic  staff  Colonel  J.  Hollis  Wells 
and  the  speaker  had  the  honor  to  serve,  as  asphalt  experts  and 
general  inspectors  of  pavements,  introduced  Trinidad  sheet  asphalt 
for  the  lower  sections  of  Madison  Avenue.  General  Greene, 
U.S.V.,  left  the  army  with  the  rank  of  captain  to  lead  the  Barber 
Asphalt  Company's  forces.  General  Averill  claimed  that  he  had 
to  spend  his  old  age  as  superintendent  of  the  Soldiers'  Home  at 
Hampton,  Va.,  through  being  defrauded  of  his  patent  rights  by 
A.  L,  Barber.  History  is  full  of  the  tragedies  of  those  who  have 
been  engaged  in  the  asphalt  business. 

"As  Highway  Commissioner  Carlisle  stated,  revolutions  have 
been  fostered,  and  bribery,  corruption  and  fraud  have  been  in  the 
wake  of  asphalt  corporations.  Fortunately,  the  European  asphalt 
companies  have  been  absolutely  clean  in  all  their  transactions. 


*Read  before  the  Highway   Engineering  Course,   Columbia  University, 
January  24th,   1914. 


I72  ASPHALTS. 

"Rock  asphalt  as  pavement  was  first  laid  in  the  United  States 
in  New  York,  in  the  fall  of  1872,  by  the  North  American  Neuchatel 
Rock  Asphalt  Paving  Company,  the  Earl  of  Dunraven,  one  of  the 
directors,  being  in  New  York  at  that  time.  Orville  Grant  was  the 
Chicago  agent,  E.  E.  Glaskin,  general  manager,  and  the  speaker, 
agent  of  the  company  for  Boston.  The  asphalt  comprime  was  laid 
on  a  Portland  cement  concrete;  about  1880  this  asphalt  comprime 
was  removed  and  taken  to  the  plant  of  the  New  York  Mastic  Works, 
then  at  the  foot  of  East  iQth  Street,  crushed,  powdered,  and,  with 
the  addition  of  asphalt  flux  made  into  mastic,  which  was  then  ap- 
plied in  the  coule  form  on  the  former  concrete  foundation;  this 
work  being  supervised  by  E.  H.  Wootton  and  myself.  In  1876  the 
District  of  Columbia  Commissioners  under  advice  of  General  H.  G. 
Wright,  Chief  of  Engineers,  decided  to  pave  Pennsylvania  Avenue 
from  the  Capitol  to  Sixth  Street  with  Neuchatel  rock  asphalt  and 
the  work  was  done  under  the  supervision  of  Matt  Taylor,  as  re- 
ceiver for  the  North  American  Neuchatel  Rock  Asphalt  Paving 
Company.  A  few  years  later,  Captain  H.  R.  Bradbury  was  sent 
to  this  country  by  the  parent  company,  the  Neuchatel  Asphalt 
Company  of  London.  He  laid  rock  asphalt  pavements  in  front 
of  the  Brevoort  House  and  the  old  Hotel  Brunswick,  both  on  Fifth 
Avenue.  About  the  year  1889,  Madison  Avenue  was  paved,  I 
believe  for  over  thirty  blocks,  with  Sicilian  Rock  asphalt  and 
several  other  streets  were  laid  at  the  same  time  with  Limmer 
asphalt  by  G.  Knoche.  In  July  1896  Convent  Avenue  from  I45th 
to  I46th  Street  was  laid  with  Sicilian  asphalt  and  is  to-day  in 
perfect  condition  after  17  years  of  traffic.  In  1892  the  Compagnie 
Generales  des  Asphaltes  de  France  erected  a  rock  asphalt  plant  at 
the  foot  of  Seventh  Street,  Long  Island  City,  under  supervision  of 
the  late  M.  Miard,  afterward  the  Compagnie's  manager  at  Cairo, 
Egypt.  Although  Thomas  F.  Gilroy,  the  then  Commissioner  of 
Public  Works  had  promised  Mr.  Delano  of  Paris,  Managing  Di- 
rector of  the  French  Company,  that  they  should  have  an  oppor- 
tunity to  bid  on  street  pavement,  the  city  specifications  were  so 
drawn  that  they  could  not  bid  on  work  and  it  was  not  until  October, 
1895,  that  specifications  allowed  of  its  use;  E.  P.  North,  Mem. 
A.  S.  C.  E.,  then  being  Water  Purveyor,  the  official  at  that  time 
in  charge  of  street  construction.  Mr.  North,  however,  insisted  on 
an  asphaltic  binder  being  used,  which  was  a  totally  unnecessary 
expense  in  the  cost  of  construction." 


CHAPTER  XXVII. 
ASPHALT    MACADAM    ROADS. 

AS  I  stated  at  Atlantic  City  in  July,  1909,  at  the  convention  of  the 
American  Society  for  Testing  Materials,  it  was*  "rather  dis- 
heartening to  be  informed  (by  a  member  of  the  Society)  that  the 
value  of  a  bituminous  cement  can  only  be  arrived  at  'by  service 
tests  for  a  number  of  years.'  As  a  practical  worker  for  nearly 
thirty-seven  years  (in  1909)  in  asphalt  construction  for  streets  and 
roads  and  for  asphalt  concrete  work  as  laid  in  foundations,  I  have 
no  hesitation  in  stating  that  with  the  use  of  such  quality  of  asphalt 
as  has  been  hitherto  satisfactorily  used  for  standard  street  asphalt 
pavements  and  with  the  mineral  aggregate  heated  and  properly 
mixed  an  entirely  satisfactory  surface  can  be  applied  to  old  or  new 
macadam  roads." 

In  1909  I  superintended  the  construction  of  School  Street, 
Washington,  D.  C,  and  several  roads  under  different  specifications 
in  Philadelphia  with  asphalt  concrete  finish. 

The  best  construction  for  asphalt  macadam  roads  is  that  cov- 
ered by  patents,  and  I  cannot  but  suggest  that  contractors  wishing 
to  lay  the  best  work  should  make  arrangements  to  obtain  conces- 
sions to  work  under  Patent  No.  727,565.  Should  they  not  wish  to 
do  so  I  can  advise  them  that  any  one  can  lay  the  asphalt  mixture 
to  which  the  name  "Topeka"  has  been  applied,  which  has  been  used 
of  late  as  a  material  suitable  for  resurfacing  water-bound  broken 
stone  roads,  as  carrying  a  certain  amount  of  fine  stone,  but  not  in- 
fringing the  F.  J.  Warren  Patent  No.  727,505.  It  owes  its  desig- 
nation to  a  ruling  in  a  case  in  litigation  in  1910  in  the  U.  S.  Dis- 
trict Court  for  the  District  of  Kansas,  in  regard  to  work  which  had 
been  done  in  the  cities  of  Topeka  and  Emporia,  Kansas.  In  this 


*Page  611,  Vol.  IX.,  Am.  Soc.  for  Testing  Materials. 


I74  ASPHALTS. 

ruling  Judge  Pollock  stated  "that  any  pavements  hereafter  con- 
structed in  substantial  with  the  following  formula,  to  wit : 

Bitumen  7—11% 

Mineral  Aggregate  passing  200  Mesh  Screen 5—11% 

Mineral  Aggregate  passing  40  Mesh  Screen 18 — 30% 

Mineral  Aggregate  passing  10  Mesh  Screen 25 — 55% 

Mineral  Aggregate  passing  4  Mesh  Screen 8 — 22% 

Mineral  Aggregate  passing  2  Mesh  Screen.. Less  than  10% 

sieves  to  be  used  in  the  order  named,  would  not  infringe  the  claims 

of  said  patent." 

All  reliable  and  experienced  engineers  and  chemists  who  have 
given  close  attention  to  the  art  of  pavement  and  road  construction 
know  that  certain  basic  qualities  are  needed  in  all  asphalt  paving 
cements  and  bituminous  road  binders.  These  basic  and  essential 
qualities  are  here  arranged  in  tabulated  form  so  that  their  separate 
importance,  correlation  and  mutual  complement  of  each  other  are 
apparent : 

1.  Adhesiveness,  or  cementing  strength 

2.  Waterproof  ness,  or  freedom  from  injury  by  water 

3.  Immutability,  or  freedom  from  deterioration  on  exposure 

to  sun  and  air 

4.  Cohesiveness 

5.  Ductility 

6.  Flexibility,  or  pliability 

7.  Malleability,  or  ability  to  yield  to  shock  without  cracking 

8.  Consistency  at  mean  weather  (77  deg.  Fahr.)  temperature, 

proper  for  the  kind  of  pavement  or  road 

9.  Minimum  susceptibility  to  softening  or  stiffening  during 

extreme  weather  temperatures 

10.  Purity,  or  high  percentage  of  bitumen 

11.  Freedom  from  impurities  of  a  vegetable  or  other  deleteri- 

ous character 

12.  Freedom  from  injury  by  heat  necessary  when  melting  for 

use. 

Waterproofness,  or  effect  of  water,  is  a  very  important  quality, 
because  pavements  and  roads  are  constantly  exposed  to  rain  and 
other  moisture  from  above,  by  capilliary  attraction  from  below,  and 
by  water  which  enters  along  and  around  rails  and  manholes,  at 
curbs  and  other  openings,  and  into  slight  cracks.  If  an  asphalt 
cement  is  not  waterproof,  vegetable  matter,  soluble  salts,  earthy 


i      I.gi    rg      §5       U    '•=    v 


S    § 


§§§ 


S         g 


Ea 

1 

o         —oo-"io          o     o         ooog,^. 

•  3  d 

E      ?0i    gS      S    g                3   ||  2 

§      agg    3U      g    S      5    5    S    3 «  O 

s    wis  Is    s§    ooi^w  d 

S      |cS    ?S       So       £•    S    5    |g|  W 


"A  S    I>   H    A    L   T    S" 


ASPHALT     MACADAM     ROADS.  175 

and  other  matter  in  it  will  decay,  the  cement  will  lose  its  binding 
strength  and  the  pavement  will  disintegrate.  All  specifications 
should  have,  like  those  of  Washington,  D.  C,  and  some  other 
places,  a  requirement  preventing  the  use  of  asphalt  cements  affected 
or  injured  by  water. 

A  carefully  prepared  form  of  test  made  necessary  to  prove  that 
bitumen  contain  these  necessary  qualifications  is  presented  on  the 
opposite  page. 


• 


BITULJTHIC     PAVEMENT. 

Dartmouth     Street,     Boston.     Mass.        Pavement     laid     1903. 
Photograph    taken   Sept.,    1913. 


WARREN  I TE     ROADWAY. 
Fairfleld   Avenue,   Fairfield,   Conn.     Laid  over  old  macadam. 


"A  S  P  H  A    L,   T   S' 


CHAPTER  XXVIII. 
COLD    LAID    ASPHALT    ROADS. 

DURING  an  experience  in  the  supervision  and  direction  of  lay- 
ing asphalt  streets  and  roads,  in  which  I  have  now  entered 
my  forty-second  year,  I  have  found  nothing  so  contrary  to  my  early 
teaching  that  asphalt  must  be  always  used  not  only  hot  and  with 
the  greatest  care  as  to  exact  temperature  required  for  different 
asphalts  and  for  different  mixtures  of  asphaltic  street  and  road 
concretes,  binders,  and  fine  street  surfaces,  as  the  fact,  that  for  the 
past  few  years,  satisfactory  results  have  been  obtained  from  the 
use  of  a  cold  mixture  of  specially  prepared  asphaltic  cement  with 
stone  and  sand  aggregate. 

Among  such  methods  of  using  cold  construction  are  those 
employed  by  companies  who  have  adopted  what  is  known  as  the 
"Westrumite"  process;  in  the  Eastern  States  it  is  little  known  and 
in  the  Highway  Engineering  Department  of  Columbia  University 
is  found  no  record  of  this  not  unimportant  branch  of  the  asphalt  in- 
dustry. The  reason  of  the  lack  of  interest  in  this  construction  is  no 
doubt  attributable  to  the  fact  that  neither  the  asphalt  nor  the  coal 
tar  trust  has  any  financial  interest  in  its  promotion. 

Several  American  visitors  to  the  exhibition  held  in  London 
in  connection  with  the  International  Roads  Congress  last  summer 
called  attention  to  the  fact  that  the  American  Westrumite  Company 
had  an  instructive  exhibit  there,  but  had  none  at  the  National  Road 
Makers'  Convention  Exhibition  in  Philadelphia  last  December; 
this  was  regrettable  as  the  congress  was  believed  to  have  been  the 
largest  attended  one  ever  held  in  the  United  States. 

My  attention  was  first  called  to  "Westrumite"*  as  an  emullsi- 
fied  oil  dust  preventative,  when  on  a  visit  to  Newark  on  Trent, 
England,  in  1904;  but  the  method  of  this  saponifying  has  since 
then  been  adopted  for  the  more  important  feature  of  affording  a 

*"Asphalts,"  page  98. 


1 78  ASPHALTS. 

cold  asphaltic-cement  or  binder  in  a  mineral  aggregate  for  asphaltic 
macadam. 

In  1911  I  visited  England  and  spent  several  weeks  in  obser- 
vation and  study  of  the  recent  methods  of  road  construction  adopted 
in  that  country.  In  the  summer  of  that  year,  "The  Road  Board" 
of  England,  through  an  arrangement  with  the  County  of  Kent  in 
collaboration  with  its  County  Engineer,  Mr.  Henry  P.  Maybury 
(since  elected  Chief  Engineer  of  The  Road  Board),  laid  twenty- 
three  experimental  strips  of  pavement  on  the  London-Folkestone 
Road  between  New  Eltham  and  Sidcup. 

Through  the  courtesy  of  Sir  George  Gibb,  Chairman  of  the 
Road  Board,  Colonel  Crompton,  Consulting  Engineer,  and  Mr. 
Maybury,  I  was  allowed  every  opportunity  of  inspecting,  observ- 
ing, and  making  inquiries  in  regard  to  the  work  of  all  the  different 
methods  of  road  construction  used  in  this  experimental  work. 

It  might  be  remarked,  en  passant,  that  Mr.  Samuel  L.  Hill, 
President  of  the  National  Road  Makers'  Association,  stated  in 
a  lecture  given  before  the  matriculated  students  of  Highway  En- 
gineering at  Columbia  University  last  December,  that  the  "Tarmac" 
and  "Pitchmac"  pavements  seemed  to  him  to  be  the  most  satis- 
factory of  the  pavements  at  the  time  of  his  inspection  of  the 
Folkestone  Road  work  in  the  midsummer  of  1913. 

Both  of  these  pavements  having  coal  tar  for  their  base  would 
certainly  have  stood  even  better  had  asphalt-cement  been  used  as 
the  cementitious  binder. 

During  my  inspection  of  the  road  in  1911  I  learned  that  while 
Messrs.  Hooghwinkle,  Anthony  Brown  and  Partners  were  invited 
to  bid  on  a  section  for  Westrumite  Asphalt  Construction,  their 
tender  was  not  accepted,  the  price  asked  there  for  maintenance 
being  considered  too  high.t 

On  my  return  to  New  York  in  July,  1911,  I  was  informed  by 
the  very  "progressive"  Park  Commissioner  Stover  that  he  had 
ordered  a  section  of  pavement  at  the  Fifth  Avenue  entrance  of 
Central  Park  to  be  laid  with  "Westrumite,"  and  inspected  the  work 
at  the  time  it  was  being  laid.  Due  to  facts,  not  reflecting  on  the  con- 
tractors, some  errors  were  made  in  delivery  of  stone,  etc.,  which 
resulted  in  the  work  not  being  up  to  standard  and  it  was  relaid  in 
1912;  it  is  now  in  good  condition,  but  a  better  sample  of  this  con- 


f'The  Road  Board  of   England  Report,"  July,   1911,  page  10. 


51 


"A   S   P   H   A    L   T   S" 


COLD    LAID     ASPHALT    ROADS.  179 

struction  can  be  seen  at  the  Ninetieth  Street  and  Central  Park 
West  entrance  to  Central  Park. 

Some  excellent  work  of  this  construction  is  reported  at  Wash- 
ington. D.  C,  and  Georgetown,  and  on  Christmas  day  I  inspected 
the  "Westrumite"  laid  at  Chevy  Chase  Circle  and  found  that  it 
compared  more  than  favorably  with  competitive  methods  of  road 
construction. 

As  stated,  this  type  of  cold  mixed  asphalt  concrete  or  macadam 
has  not  been  used  in  the  East  to  the  extent  that  it  has  been  in 
the  Western  States  and  in  Canada,  where  excessive  climatic  changes 
are  more  trying  to  the  life  of  such  pavements. 

Enconiums  on  work  done  are  found  from  such  well-known 
road  experts  as  Messrs.  C.  K.  Wallace,  City  Engineer,  East  Chi- 
cago, Ind. ;  J.  Boyer,  City  Engineer,  Crookston,  Minn. ;  H.  Fergu- 
son, B.S.,  C.E.,  Stratford,  Ont. ;  A.  McGillivray,  Government 
Highway  Commissioner,  Winnipeg,  Manitoba;  Peter  J.  Lyons,  City 
Engineer,  Hammond,  Ind. 

In  Europe  noticeable  work  has  been  laid  in  Antwerp  and  in 
Lambach  and  Graz,  Austria. 

The  possibilities  of  using  such  cold  construction  as  this  in 
places  where  it  is  difficult  to  transport  machinery  for  heating 
asphalt  and  where  work  is  required  in  small  areas  and  inaccessible 
sections  of  country,  makes  the  study  and  investigation  of  this 
cold  process  one  of  great  interest  to  highway  commissioners  and 
other  authorities  having  charge  of  road  construction. 

The  only  patent  in  connection  with  Westrumite  Asphalt  Pave- 
ment is  for  the  emulsifying  of  bitumens  by  which  it  is  made,  and 
even  this  is  in  no  sense  monopolistic  as  there  are  several  inde- 
pendent companies  within  the  United  States  and  Canada  manu- 
facturing and  marketing  this  product  at  their  own  prices. 

The  specifications  under  which  it  is  being  recommended  for 
road  construction  are  adaptable  to  the  use  of  this  particular  ma- 
terial. There  is,  however,  no  obligation  on  the  part  of  any  purchaser 
to  use  these  specifications. 

ttWestrumite  Asphalt  is  adaptable  to  road  uses  in  three  dif- 
ferent methods  of  construction,  two  of  which  have  one  basic  prin- 
ciple: the  thorough  and  positive  bonding  together  of  mineral  ag- 


tfGood   Roads   Year   Book   of   American    Highway   Association,    1913, 
page  361. 


l8o  ASPHALTS. 

gregate  ranging  in  size  from  two  inches  to  one  inch  by  the  intro- 
duction of  bituminous  mortar  composed  of  aggregate  varying  in 
size  from  that  which  will  pass  the  one-half-inch  opening  to  an 
impalpable  dust  in  proper  proportions  to  assure  greatest  density, 
mixed  with  a  proper  proportion  of  same  asphalt. 

Although  the  principle  used  and  the  results  are  practically  the 
same,  the  methods  of  their  accomplishment  slightly  differ. 

In  the  one,  on  any  form  of  solid  and  approved  foundation 
such  as  concrete,  crushed  stone  properly  compressed  or  new  or  old 
macadam,  the  two  inch  to  one  inch  stone  is  thoroughly  coated 
with  the  Westrumite  Asphalt  and  spread  to  a  thickness  of  two 
inches,  but  in  no  way  is  to  be  compacted  allowing  the  existence  of 
the  maximum  amount  of  voids  or  air  spaces  around  them.  Upon 
these  stones  then  is  spread  the  mortar,  as  previously  described,  to 
a  depth  of  one  inch,  having  a  consistency  of  very  thick 
molasses,  which  on  account  of  its  fluid  consistency  largely  fills  the 
voids  about  the  two-inch  stone.  Such  voids  as  are  not  thoroughly 
filled  in  this  manner  are  filled  when  the  surface  is  rolled  with  an 
asphalt  roller  weighing  from  five  to  eight  tons  until  the  bituminous 
materials  applied  have  been  thoroughly  compacted  and  left  smooth. 

Upon  this  surface  is  applied  a  very  light  coat  of  same  asphalt 
cement  to  fill  and  seal  any  small  voids  and  interstices  that  may 
exist,  on  to  which  before  the  cement  becomes  set,  is  spread  a  thin 
layer  of  clean  stone  chips  varying  in  size  from  three-eighths  to 
one-eighth  inch.  The  pavement  is  again  thoroughly  rolled  and  in 
about  forty-eight  hours,  permitting  the  same  asphalt  to  become 
thoroughly  "set,"  is  ready  for  traffic. 

The  second  method  of  construction,  particularly  adaptable  to 
the  resurfacing  of  new  or  old  macadam  roads,  is  identical  to  the 
method  described,  excepting  that  the  two  inch  to  one  inch  stone  is 
not  coated  with  Westrumite  Asphalt.  In  this  method  the  macadam 
road  to  be  treated  is  scarified  or  harrowed  to  a  depth  of  two  to 
three  inches,  all  particles  of  stone  smaller  than  the  three-fourths 
inch  thus  sifting  to  the  bottom,  leaving  the  coarse  stone  at  the  top 
uncompressed  and  containing  maximum  amount  of  voids.  Upon 
this  surface  then  is  spread  the  bituminous  mortar,  as  described  in 
the  foregoing,  with  the  finish  or  flush  coat  handled  in  the  same 
manner. 

The  third  method  of  construction  consists  of  a  surface  treat- 
ment of  macadam  roads. 


COLD     LAID     ASPHALT    ROADS.  181 

The  road  to  be  treated  should  be  thoroughly  cleaned  of  all 
small  particles  by  brooming,  until  the  coarse  stone  is  exposed  to 
view,  when  Westrumite  Asphalt  is  to  be  applied  by  use  of  pouring 
cans  or  pressure  distributer  in  proper  quantity. 

Upon  the  asphalt  cement  thus  applied,  should  immediately  be 
spread  stone  screenings  free  from  clay  in  varying  sizes  from  one- 
half  inch  to  impalpable  dust  in  sufficient  quantity  to  "take  up"  or 
absorb  the  asphalt.  This  is  then  thoroughly  rolled  until  left  smooth 
and  compact. 

This  surface  is  then  covered  with  a  very  light  application  of 
asphalt  into  which  is  spread  and  rolled  a  light  covering  of  clean 
stone  chips  varying  in  size  from  the  three-eighths  to  one-eighth 
inch  with  the  surface  again  thoroughly  rolled.  Traffic  should  be 
restricted  for  about  forty-eight  hours  to  permit  the  asphalt  to 
become  set. 

While  this  article  treats  almost  entirely  of  one  process  for  cold 
application  there  are  of  course  other  methods  and  other  mixtures 
which  can  be  used  cold  on  the  line  of  work. 

In  Pennsylvania,  New  Jersey,  and  Ohio,  several  miles  of  road 
have  been  laid  with  a  mixture  of  stone  and  asphalt  binder  mixed 
hot  at  the  stone  quarries  but  shipped  cold  and  so  spread  on  the 
roads. 

In  the  Folkestone  Road  experimental  work,  several  cold  appli- 
cations were  made,  among  which  was  the  crude  Seyssel  Rock 
Asphalt  broken  to  small  lumps  and  compressed  by  rolling.  The 
work  did  not  prove  satisfactory  and  I  continue  to  believe  that  rock 
asphalt  should  always  be  heated  to  obtain  the  best  results. 

The  "Tarmac"  referred  to  is  also  shipped  and  applied  cold, 
being  constituted  of  slag  coated  and  permeated  while  still  hot  from 
the  steel  furnaces  with  bituminous  binder.  Coal-tar  has  been  one 
of  the  ingredients,  but  asphalt-cement  of  proper  consistency  would 
give  better  results. 

In  this  country**  crude  asphaltic  sandstone,  shipped  as  a  cold 
powder,  has  given  excellent  results  and  in  some  sections  of  the 
country  gives  an  opportunity  for  a  moderate  cost  surface  to  an 
ordinary  macadam  road. 

A  method  not  yet  advocated  in  this  country  in  the  cold  pro- 

**U.   S.   Department  of  Agriculture,   Office  of  Public  Roads,   Circular 
No.  99,  page  51. 


lg2  ASPHALTS. 

cess  of  laying  asphalt  macadam  is  asphalt  tarmac.  It  appears  to 
be  generally  conceded  that  our  visitors  to  the  International  Road 
Congress  held  in  London  last  June  considered  that  the  most  dur- 
able and  desirable  road  in  England  was  the  tarmac.  The  writer 
saw  the  material  being  laid  on  the  famous  experimental  section  of 
the  Folkestone  Road  between  New  Sidcup  and  Eltham.  The  sec- 
tion was  laid  in  July,  1911,  by  the  Kent  County  Council  under 
arrangement  with  the  Road  Board  of  England,  under  specifications 
of  H.  P.  Maybury,  the  County  Surveyor  of  Kent;  Col.  R.  E. 
Crompton  being  consulting  engineer  to  the  Board ;  Sir  Charles  Gibb 
Charman  and  F.  W.  Greig,  resident  engineers. 

The  aggregate  of  "tarmac"  consists  of  selected  blast  furnace 
slag  produced  for  use  at  the  Tarmac  Company's  works  adjacent 
to  the  furnaces  of  Sir  Alfred  Hickman,  Ld.,  Springvale,  Etting- 
shall,  near  Wolverhampton.  The  author  visited  the  works  and 
made  a  careful  study  and  examination  of  everything  in  connection 
with  the  preparation  of  this  bituminous  macadam  for  shipment 
to  London.  This  slag  is  run  in  a  molten  state  from  the  furnaces 
Into  suitable  receptacles.  In  these  receptacles  it  is  shunted  on  to 
the  company's  premises  adjacent  to  the  furnaces  and  there  allowed 
to  remain  until  in  the  process  of  cooling  it  has  solidified.  It  is 
then  tipped  on  the  slag  selecting  ground  in  blocks  of  about  5  tons 
each,  broken  by  hand  into  pieces  of  suitable  size,  conveyed  to  the 
company's  crusher,  which  turns  out  the  different  sizes  from  2^4 
inches  to  %  inch,  which  is  graded  and  then  treated  with  the  "Tar- 
mac" bituminous  or  asphalt  composition. 

By  this  process  the  slag  up  to  the  time  that  is  is  impreg- 
nated with  the  Tarmac  cement,  has  had  no  opportunity  of  absorb- 
ing moisture  and  therefore  at  the  time  of  treatment  is  perfectly  dry. 

Never  having  cooled,  no  reheating  is  necessary,  and  the  tem- 
perature at  the  time  of  treatment  with  the  Tarmac  cement  can  be 
uniformly  regulated. 

The  slab  used  breaks  with  a  very  rough  and  uneven  fracture 
and  therefore  has  the  greatest  holding  capacity  for  the  bituminous 
cement.  It  is,  moreover,  sufficiently  porous  to  absorb  and  hold  a 
portion  of  the  mixture.  "Tarmac"  is  broken  to  the  following 
gauges : 

2l/4  inches  (2%    inches    down    to    1^2    inches) 
i}^  inches  (il/2  inches  to  l/2  inch) 
•Hi  inch   (^  inch  to  H  inch) 


52 


"A  S  P  H   A  L,  T  S 


COLD    LAID     ASPHALT    ROADS.  183 

and  shipped  from  the  works  in  railroad  cars  ready  for  immediate 
use  on  the  line  of  road  work  without  heating,  to  any  town  in 
England. 

The  binding  cement  used  for  coating  the  slag  is  the  Tarmac 
Company's  special  bituminous  cement,  or  a  pure  asphalt.  The 
Ettingshall  works  have  a  complete  distillation  plant,  and  the  mix- 
ture is  prepared  to  certain  uniform  chemical  and  physical  standards 
which  are  known  to  give  the  best  results  as  regards  binding, 
strength,  durability  and  resistance  to  atmospheric  changes. 

Upon  the  prepared  road  surface  a  bottom  coat  of  2^4  mch 
gauge  material  is  applied  and  consolidated  to  a  thickness  of  2l/2 
inches.  Upon  this  an  upper  coat  of  il/2  inch  gauge  material  is 
applied  to  consolidate  to  a  finished  thickness  of  il/z  inches,  making 
the  total  thickness  of  the  double  coating  4  inches.  Each  layer  is 
separately  consolidated  with  a  steam  roller,  6  to  8  tons  in  weight, 
and  the  surface  of  the  top  layer,  after  half-consolidation,  is  well 
brushed  over  with  y%  inch  gauge  "Tarmac"  so  as  to  fill  all  inter- 
stices and  is  then  rolled  to  an  even  and  watertight  surface,  being 
afterwards  covered  with  slag  chippings  at  the  rate  of  one  ton  to 
cover  250  super  yards. 

No  special  tools  other  than  those  usually  employed  by  local 
authorities  are  required.  The  after-consolidation  which  takes  place 
under  traffic  varies  with  the  original  thickness  and  the  nature  of 
the  traffic  on  the  road. 

The  thickness  of  4  inches  is  that  recommended  for  very  heavily 
trafficked  roads.  For  most  main  roads  a  smaller  thickness  at  a 
reduced  cost  of  construction  may  be  used. 

This  system  of  finished  surface  is  free  from  dust  in  summer 
and  mud  in  winter,  is  non-slippery,  practically  noiseless,  resilient, 
and  impervious  to  ordinary  atmospheric  conditions  or  changes. 

''Tarmac"  can  be  applied  with  equal  success  at  any  season  of 
the  year,  some  of  the  best  work  in  Nottinghamshire  having  been 
laid  in  winter.  Work  can  be  proceeded  with  during  wet  weather, 
the  only  stoppage  necessary  being  in  drenching  rain  when  men 
refuse  to  work,  or  when  foundations  of  a  soft  or  clayey  nature  have 
become  saturated  with  wet. 

The  material  is  impervious  to  wet  when  sent  out  from  the 
works.  There  is,  unfortunately,  no  method  of  giving  the  approxi- 
mate cost  of  the  work  in  the  United  States,  the  Carnegie  Steel  Com- 


184  ASPHALTS. 

pany  having  held  up  a  proposition  to  install  a  plant  in  connection 
with  one  of  their  works  for  a  period  of  over  two  years. 

The  figure  obtained  for  the  "Tarmac"  work  on  the  Folkestone 
Road  was  97  cents  per  square  yard,  which  included  6  cents  per 
superficial  yard  for  preparation  of  surface,  but  ordinarily  it  can 
be  laid  on  the  old  road  surface.  The  figure  also  included  the  cost 
of  three  annual  dressings  of  "Tarmac"  liquid  cement  with  slag 
clippings;  which  work  although  not  essential  to  carry  the  road 
through  its  life,  has  by  experience  been  found  to  be  of  great 
permanent  benefit. 

It  would  seem  probable  that  the  cost  of  $i  per  square  yard 
would  not  be  exceeded  in  places  where  low  freights  prevail  from 
the  steel  furnaces  to  towns  or  villages  where  cold  laid  pavements 
are  the  desideratum.  As  early  as  September,  1911,  the  author  re- 
ceived reports  from  England  that  the  "Tarmac"  was  the  most 
satisfactory  of  the  experimental  strips  of  pavement  on  the  Folke- 
stone Road,  and  the  same  satisfactory  result  was  reported  as  exist- 
ing in  July,  1913,  by  the  Hon.  Samuel  J.  Hill  in  his  lecture  last 
December  before  the  graduate  students  of  the  Highway  Engineering 
course  of  Columbia  University.  This  material  and  the  machinery 
for  its  preparation  were  originally  patented  by  Mr.  E.  Purnell 
Hooley,  the  County  Surveyor  of  Nottinghamshire. 

Another  cold  process  for  road  surface  construction  is  to  be 
found  in  the  natural  Kentucky  rock  asphalt  sandstone  which  in  pow- 
der form  can  be  shipped  in  open  freight  cars  from  Bowling  Green, 
Ky.,  and  applied  to  a  levelled  surface  of  an  old  macadam  road  at 
an  economical  figure  for  use  in  towns  to  which  reasonable  freight 
rates  can  be  obtained.  Detroit  and  Buffalo  may  be  instanced.  A 
report  prepared  by  the  office  of  Public  Roads  and  issued  June  3Oth, 
1913,  says  in  regard  to  the  experimental  stretch  of  pavement  laid 
at  Bowling  Green,  Kentucky  in  1907: 

"The  surface  in  general  remains  intact,  smooth  and  hard,  but 
bears  evidence  of  not  having  had  any  attention.  The  slight  defects 
found  can  be  repaired  at  a  very  small  cost  and  the  section  thus 
put  in  excellent  condition/' 

This  is  a  good  report  after  six  years  of  service. 

The  Texas  asphalt  rock  from  Uvalde  Co.  can  also  be  pow- 
dered and  shipped  to  sections  where  moderate  freight  charges  can 
be  obtained,  and  should  give  even  better  results  than  the  Kentucky 
as  it  is  a  limestone  in  place  of  a  sandstone. 


"A  S   P  H  A  L,   T   S' 


CHAPTER  XXIX. 
BITUMINOUS    ROAD    SURFACES.* 

IN  1909  I  was  elected  as  the  delegate  to  the  American  Road 
Makers'  Convention  at  Cleveland,  Ohio,  to  represent  the  Quaker 
City  Motor  Club,  that  organization  having  always  shown  a  keen 
interest  in  the  building  and  maintenance  of  the  "best  roads."  It 
was  eminently  proper  that  they  should  at  the  time  mentioned  seek 
to  know  of  every  improvement  possible  in  road  construction,  for 
it  was  just  prior  to  their  holding  the  great  Quaker  City  Motor  Race 
in  Fair-mount  Park,  which  was  attended  by  one  million  visitors, 
Messrs.  L.  W.  Page,  Wilson,  and  the  speaker  being  their  special 
committee  on  the  condition  of  the  eight  miles  of  road  over  which 
the  race  was  to  be  run.  The  Quaker  City  Motor  Club  desires, 
through  me,  to  make  the  following  suggestions  in  regard  to  the 
construction  of  concrete  roads : 

All  concrete  roads  to  have  ample  provision  for  expansion 
joints,  such  as  those  lately  adopted  at  the  navy  yard,  Norfolk, 
Virginia,  manufactured  from  felt  in  sandwich  form  with  bitumen 
in  the  center,  or  the  cold  asphalt  prepared  joints  of  straight  bitumen 
formed  in  strips  of  regular  width.  All  concrete  roads  to  have 
a  resilient,  noiseless,  waterproof  coating. 

The  statement  in  "Rock  Products,"  issue  of  February  12,  "the 
necessity  of  firm  unyielding  roads  under  present-day  traffic  con- 
ditions, has  resulted  in  a  wide  demand  both  on  the  part  of  the 
engineering  profession  and  the  public,  for  more  accurate  and  more 
scientific  knowledge  of  the  serviceability  and  permanency  of  various 
types  of  roads,"  is  inaccurate  insofar  as  it  refers  to  "firm,  un- 
yielding roads,"  which  should  be  religiously  avoided.  The  failures 
the  speaker  has  witnessed  in  cement  construction  of  roads,  starting 
in  1886,  when,  as  civic  aide  to  Gen.  John  Newton,  formerly  Chief 
of  Engineer  Corps,  U.  S.  A.,  he  supervised  the  laying  of  a  Portland 
cement  concrete  street,  put  down  by  an  English  corporation  on 

*  Read  before  the  Concrete  Road  Conference,  Chicago,  Feb.  13,  1914. 


186  ASPHALTS. 

Beaver  Street,  north  of  the  Produce  Exchange,  New  York,  and 
which  did  not  last  six  months,  down  to  the  present  time,  convinces 
him  that  the  Hassam  Paving  Company  was  correct  when  it  changed 
its  form  of  specification  and  called  for  a  bituminous  surface. 

The  claim  of  the  Dolarway  Company  for  a  patent  for  using 
material  from  the  Barrett  Manufacturing  Company  plants,  has, 
the  speaker  believes,  been  disallowed.  While  the  subject  of  bitum- 
inous material  best  suited  for  the  surfacing  of  concrete  roads  is 
being  considered,  I  should  like  to  call  the  attention  of  highway 
commissioners  to  the  fact  that  pure  liquid  asphalt,  or  maltha,  can 
be  obtained  at  about  as  reasonable  a  figure  as  Tarvia,  Ugite,  and 
other  coal  products,  and  with  much  greater  lasting  results. 

Another  treatment  of  concrete  surfaces  has  lately  been  mooted, 
and  the  speaker  begs  to  bring  it  before  the  notice  of  this  confer- 
ence. By  the  use  of  "Impervite"  in  the  upper  stratum  of  a  con- 
crete road,  not  only  a  waterproofing  process  is  obtained,  but  from 
tests  made  in  Washington,  it  has  been  shown  that  a  certain  resili- 
ency results,  added  to  an  increased  crushing  strength. 

It  must  be  emphasized  that  with  a  lean  mortar,  the  perma- 
nency of  the  waterproofing  compound  is  a  very  important  point. 
That  class  of  compound  using  stearate,  leates,  resinates,  or  other 
soapy  material  as  a  base,  gradually  washes  out  under  prolonged 
action  of  water  which  slowly,  but  surely,  dissolves  even  stearate 
of  lime.  A  permanently  waterproof  surface  is  dependent  on  using 
a  compound  that  is  absolutely  insoluble  and  unaffected  by  the 
elements.  Bituminous  waterproofing  products  belong  to  this  class, 
and  compounds  have  been  developed  which,  as  miscible  with  water, 
yet  become  absolutely  insoluble  after  the  mortar  has  set.  This 
result  is  obtained  by  emulsifying  the  bitumen,  which  then  mixes 
with  water. 

Bituminous  materials,  so  prepared,  give  a  very  high  degree  of 
permanent  waterproofing.  They  are  absolutely  unaffected  by  salt 
water,  brine,  running  water,  boiling  water,  and  ordinary  chemicals. 

Liquid  asphalt  for  oiling  roads  is  applied  not  only  to  surface 
of  macadam  roads  but  also  on  ordinary  dirt  and  gravel  roads  with 
excellent  results. 

The  presence  of  a  large  percentage  of  pure  asphalt  in  the 
liquid  gives  it  a  quality  necessary  for  making  a  fine  type  of  road- 
way surface. 

The  lighter  or  volatile  constituent  causes  the  asphalt  to  pene- 


PRIVATE     ESTATE.     GLENCOVE,      I,.     I. 

Roads    treated    with    Aztec    liquid    asphalt. 


d    STREET     KETWEEX     HROADWAY    AND    COLUMBUS    AYE..     XE\V    YORK    CITY 
Aztec-    sheet    asphalt    pavement. 


"A   S   P  H    A    L  T   S' 


BITUMINOUS     ROAD     SURFACES.  187 

tiate  well  into  the  surface  of  the  roadway.  Upon  evaporation  of 
this  volatile  element,  the  asphalt  remaining  forms  a  strong  binder 
and  firmly  holds  the  mineral  particles  of  the  roadway  together 
making  a  hard,  plastic  and  durable  surface. 

Practice  has  shown  that  paraffine  oils  or  semi-asphaltic  petro- 
leum containing  a  high  percentage  of  paraffine  are  of  no  benefit  to 
a  roadway.  The  temporary  result  of  having  the  dust  laid  by  such 
oils  is  of  no  value  to  the  wearing  qualities. 

Liquid  asphalt  is  not  only  a  road  preservative  but  a  construc- 
tive ag^nt  as  well.  Applied  to  a  macadam  roadway  this  material 
will  make  a  compact  and  lasting  surface. 

Liquid  asphalt  may  be  obtained  in  two  grades,  "A"  and  "B." 

"A"  is  for  cold  application  and  "B"  is  to  be  applied  hot. 

Directions  for  Applying  Liquid  Asphalt  "A" 

The  surface  of  the  macadam  roadway  should  be  carefully 
swept  with  stiff,  hard  brooms,  removing  all  surface  dirt  as  well  as 
the  stone  or  sand  filling.  On  this  rough,  clean,  dry  surface  liquid 
asphalt  should  be  applied  cold  to  the  extent  of  about  one-third  of  a 
gallon  to  a  square  yard.  After  the  liquid  has  been  applied,  a 
covering  of  dustless  screenings  or  coarse  sand  should  be  spread 
upon  the  roadway. 

On  roads  of  very  light  traffic,  the  liquid  asphalt  can  be  applied 
in  diminished  quantities,  in  which  case  it  would  not  be  necessary 
to  use  the  stone  screenings  or  sand.  When  applied  without  the 
covering  of  stone  screenings  or  sand  the  quantity  of  liquid  asphalt 
applied  should  be  at  the  rate  of  about  one-eighth  of  a  gallon  to 
one-fifth  of  a  gallon  to  the  square  yard. 

Directions  for  Applying  Liquid  Asphalt  "B." 

Liquid  asphalt  "B"  should  be  applied  when  heated  to  a  tem- 
perature of  about  250  degrees  F. 

As  in  the  case  of  the  cold  application,  the  surface  of  the 
macadam  roadway  should  be  carefully  swept  to  remove  all  dirt 
as  well  as  the  stone  or  sand  filling.  On  this  rough,  clean,  dry 
surface  a  coating  of  liquid  asphalt  "B"  is  spread,  using  about 
one-fifth  to  one-third  of  a  gallon  per  square  yard.  It  should  be 
applied  by  hand  sprinkling  pots  or  spread  on  by  specially  devised 
pressure  sprinklers.  It  should  then  be  covered  with  a  layer  of 
$4  inch  stone  or  dustless  screenings  and  thoroughly  rolled.  It  is 


!88  ASPHALTS. 

not  advisable  to  make  this  application  when  the  weather  is  wet 
or  cold. 

Liquid  asphalt  has  been  used  in  treating  roads  in  a  number 
of  towns  in  New  York  and  New  Jersey.  The  treatment  does  not 
consist  in  forming  a  bituminous  carpet  over  the  road,  as  this  is 
understood  in  Massachusetts  for  example,  where  heavy  asphalts 
are  applied  hot  to  the  road  bed  and  form  a  distinct  bituminous  layer 
of  asphalt  and  stone  screenings.  With  the  use  of  the  liquid  asphalt 
as  described,  on  account  of  the  lightness  of  the  material  there  is 
an  actual  penetration  of  the  oil  into  the  material  of  the  road  and 
the  heavier  bitumens  form  a  crust  which  increases  in  thickness  with 
successive  years'  applications. 

The  experience  of  the  town  of  Islip,  Long  Island,  is  typical 
of  the  general  method.  Here  liquid  asphalt  of  about  20°  Baume 
gravity  was  used.  This  material  is  a  natural  or  "straight  run"  as 
distinguished  from  a  "cut  back"  material.  Consequently  it  is  com- 
posed of  hydrocarbons  of  more  nearly  uniform  density  than  is 
"cut  back"  material. 

For  about  eight  years  the  oil  treatment  has  been  used.  Pre- 
vious to  that  the  roads  had  been  sprinkled  with  water  by  private 
contract,  presumably  at  a  high  cost,  as  at  times  they  required 
sprinkling  five  times  a  day.  One  treatment  of  oil  a  year  has  been 
sufficient.  Last  year  about  one  hundred  miles  were  oiled  at  a  cost 
of  about  $8,500.  The  amount  of  asphalt  used  is  about  one-third 
gallon  per  square  yard.  It  was  applied  by  a  Studebaker  distributor, 
under  power  from  a  pump  operated  through  chains  and  gears  from 
the  wheel. 

The  most  unique  surfacing  for  roads  that  I  have  come  across 
is  one  on  a  dirt  by-road  near  Fort  Stevens,  in  the  District  of  Colum- 
bia near  the  Maryland  line,  where  I  found  last  February  that  some 
enterprising  individual  had  covered  about  150  running  feet  of  sur- 
face with  the  material  stripped  from  a  slag  roof — the  paper  surface 
of  the  roofing  was  uppermost  and  the  slag  and  tar  on  the  road  top. 
The  sun  will  doubtless  melt  the  tar  and  the  slag  will  become  de- 
tached from  the  felt,  which,  presumably,  will  be  blown  away  or 
possibly  be  raked  off. 


ALBANY    POST    ROAD.       NORTH    TARRYTOWX. 
Laid    with    Hastings    Asphalt    Blocks. 


BOSTON    POST    ROAD.        IN    THE    VILLAGE    OF    RYE. 
Laid    with    Hasting   Asphalt    Blocks. 


'A  S  P  H  A   L   T   S 


CHAPTER  XXX. 
ASPHALT  BLOCKS  FOR  ROADS. 

A  CONSTRUCTION  which  may  be  used  for  the  wearing  sur- 
face of  rural  roads,  is  one  that  can  be  manufactured  at  a 
permanent  plant,  and  shipped  in  block  form  to  the  site  of  the 
proposed  improvement,  ready  to  lay,  and  which  can  be  obtained  in 
small  or  large  quantity  at  any  time  for  extension  or  repairs. 

Many  years  ago  the  asphalt  block  was  developed  on  the  theory 
that  crushed  trap  rock,  on  account  of  its  pre-eminent  hardness  and 
inherent  grittiness,  made  the  best-known  material  for  a  roadway 
surface,  the  one  thing  needed  being  a  cement,  or  binding  material, 
to  keep  all  the  particles  permanently  in  place.  This  was  accom- 
plished by  the  use  of  an  asphaltic  cement  to  bind  together  the 
properly  graded  particles  of  crushed  trap,  the  hot  mixture  being 
consolidated  by  tremendous  pressure  into  blocks  so  dense  and  free 
from  voids  as  to  be  practically  non-absorbent.  In  the  asphalt-block 
we  have  an  asphaltic  concrete,  or  macadam,  mixed,  in  exact  pro- 
portions, at  a  central  plant,  under  conditions  insuring  uniformity, 
and  receiving  the  compression  necessary  to  produce  a  dense  and 
non-absorbent  material. 

The  blocks  thus  made  are  ready  for  immediate  shipment  to 
the  location  of  the  proposed  improvement,  whether  it  be  only  a  few 
hundred  square  yards  or  many  thousand  square  yards.  The  ex- 
pense of  shipment  is  no  greater  than  would  be  the  cost  of  shipping 
the  crushed  trap  rock  necessary  for  constructing  an  equivalent 
amount  of  ordinary  macadam. 

As  designed  and  manufactured  for  use  on  country  roads,  the 
blocks  are  five  inches  wide,  twelve  inches  long,  and  two  inches 
deep  (5  in.  x  12  in.  x  2  in.),  weighing  about  eleven  pounds  each. 

Not  only  has  a  special  block  been  produced,  but  a  special 
method  of  construction  has  been  worked  out,  designed  to  utilize 
what  is  left  of  the  worn  and  rutted  macadam  road  as  a  foundation 
for  the  blocks.  This  is  accomplished  by  scarifying  the  surface,  if 


190 


ASPHALTS. 


necessary,  filling  up  the  deep  ruts,  rolling  with  a  heavy  steam  roller, 
and  laying  upon  the  surface  of  the  old  macadam,  a  bed  of  cement 
mortar  about  one  inch  in  thickness,  to  serve  the  double  purpose  of 
forming  a  firm,  unyielding  bed  for  the  blocks,  and  binding  them 
securely  to  the  macadam  foundation  underneath.  By  this  method 
the  material  used  in  the  original  construction  of  the  road  is  not 
thrown  away,  but  used  as  foundation  for  a  permanent  wearing 
surface.  Where  the  old  macadam  is  too  thin,  or  too  badly  worn  to 
be  safely  used  as  a  foundation,  it  will  be  necessary  to  lay  a  con- 
crete base,  but  usually  there  is  broken  stone  enough  in  the  old 
macadam  to  supply  what  is  needed  for  laying  concrete. 

Another  advantage  gained  by  the  use  of  blocks  lies  in  the 
feasibility  of  laying  a  pavement  of  any  desired  width,  contour, 
grade,  or  crown.  It  is  feasible  to  pave  one-half  of  the  roadway,  or 
only  a  narrow  strip  in  the  center,  and  extend  the  paved  area  at  a 
later  date  as  traffic  necessities  require,  or  as  appropriations  become 
available.  It  is  not  necessary  to  set  curbstones  or  heading  stones  to 
border  or  define  the  paved  area,  since  a  row  of  stretcher  blocks 
held  firmly  in  place  by  a  shoulder  of  mortar,  answers  the  purpose 
perfectly  and  leaves  the  entire  roadway  surface  smooth  and 
uniform. 

This  system  of  road  construction  for  heavy  travel  inter-urban 
highways  has  now  acquired  a  reputation  for  efficiency.  The  Albany 
Post  Road  running  up  the  valley  of  the  Hudson  River  and  the 
Boston  Post  Road  running  along  the  shore  of  Long  Island  Sound 
have  sections  surfaced  with  these  blocks. 

As  stated  in  Chapter  26  the  use  of  European  Natural  Rock 
Asphalt  blocks,  or  as  they  are  called  in  Europe,  paves  or  slabs,  is 
likely  to  become  an  important  feature  in  road  construction.  The 
duty  on  Rock  Asphalt  Powder  which  was  in  1913  three  dollars 
per  ton,  has  been  removed,  and  it  is  now  possible  to  compress  the 
blocks  in  the  United  States  and  sell  them  at  a  lower  cost  than  can 
be  made  in  any  of  the  European  capitals.  The  specifications  for 
the  imported  slabs  as  laid  on  Thomas  Street,  New  York,  were  as 
follows : 

The  Portland  cement  concrete  base  to  receive  the  paves  should 
be  either  four  (4)  or  five  (5)  inches  in  thickness,  furnished  in 
place  properly  struck  off,  smooth,  parallel  to,  a  specified  distance 
of  21/4  inches  below  the  final  grade.  On  this  lay  a  one  (i)  inch 
cushion  coat  or  bed  of  Portland  cement  and  sand,  mixed  dry,  in  the 


ASPHALT    BLOCKS     FOR     ROADS.  191 

proportions  of  i  to  3,  of  just  sufficient  thickness  to  level  up  the 
inequalities  of  the  concrete  base  underneath,  so  as  to  afford  a 
perfectly  level  surface  for  the  paves.  These  paves  are  to  be  laid 
with  the  joints  close  together  and,  when  all  are  laid,  the  surface 
of  the  paves  is  watered  with  a  sprinkling  can,  so  that  sufficient 
moisture  may  penetrate  between  the  joints  of  the  paves  to  enable 
the  cement  and  sand  under  the  paves  to  set  up. 

The  entire  surface  of  the  paves  is  then  covered  with  a  rubber 
coat  of  European  Rock  Asphalt  Mastic,  laid  about  3/16  inch  in 
thickness. 

The  object  of  the  rubber  coat  is  to  close  the  joints  of  the 
paves  while  they  are  undergoing  their  ultimate  compression  under 
the  traffic  and  also  to  afford  an  absolutely  safe  foot-hold  to  horses^ 
etc.,  during  wet  or  slippery  weather. 

Owing  to  this  coating  being  composed  almost  entirely  of  pure 
European  Rock  Asphalte,  it  forms  a  tough,  rubbery  coating  which 
indents  easily  under  the  horses  feet  but  does  not  break,  thereby- 
affording  an  absolutely  sure  foothold  in  turning  and  backing. 

These  paves  or  slabs  come  in  two  sizes : 

8  in.  x8  in.  x  il/2  in.  and  weigh  about  7^  Ibs.  each. 
10  in.  x  10  in.  x  i^  in.  and  weigh  about  12^4  Ibs.  each. 

A  project  is  on  foot  to  utilize  the  Texas  asphalt  for  the  manu- 
facture of  asphalt  blocks,  and  there  is  no  question  but  that  with 
pressing  machines  established  at  the  Uvalde  mines,  blocks  could  be 
manufactured  which  might  be  put  on  board  at  Galveston  and 
shipped  at  a  moderate  cost  for  use  at  seaport  towns  in  the  United 
States,  Cuba,  the  West  Indies  and  South  America. 


ADVERTISEMENTS. 


JOHN  BAKER,  Jr. 

REFINED  ASPHALT 

FOR  PAVING  AND 
ROAD    BUILDING 

And  All  Other  Purposes 


NEW  YORK  OFFICE 
Whitehall  Building,  17  Battery  Place 


CHICAGO  OFFICE 
Otis  Building,  10  S.  La  Salle  Street 


OTHER  OFFICES 

BOSTON  KANSAS  CITY,  MO. 

PITTSBURG  MINNEAPOLIS,  MINN. 

PHILADELPHIA  DENVER,  COLORADO 

BUFFALO  BIRMINGHAM,  ALA. 

RICHMOND  ALBANY,  N.  Y. 


Representatives  throughout  United  States  and  Canada 

WRITE  FOR  PARTICULARS 


ADVERTISEMENTS. 


A  proper  connection. 


High  standard    requirements: 


TEXACO 


PAVING 

WATERPROOFING 
ROOFING 


ASPHALT 


Good  work  and  satisfied  customers. 


Uniform.         Durable.  Pure. 

Write  to  Dept.  A. 

The  Texas  Company 

New  York          Philadelphia          Providence          St.  Louis 
New  Orleans,  and  Port  Arthur,  Houston  and  Dallas,  Texas 


ADVERTISEMENTS. 


WARRENITE  -THE  PERMANENT  COUNTRY  ROAD  SURFACE 


(Gravel) 


(Crushed  Stone) 


(Oyster  Shells) 


The  above  illustration  shows  vertical  sawed  cross  sections  of  Warrenite,  the  permanent 

country  road  surface,  using 
A-Gravel  ) 

B— Crushed  Stone  \  Mineral  Aggregates 
C-Oyster  Shells    ) 
All  of  which  have  proven  to  give  satisfactory  results. 

See  illustration  opposite  page  176  of  text. 

Warrenite  is  not  a  mere  liquid  coating  but  is  a  hard  surface  made  of  a  dense  mixture 
of  stone  heated  and  combined  with  bituminous  cement  and  laid  two  inches  in  thickness. 

INVESTMENT  versus  SPECULATION 
BITULITHIC    FOR   CITY    STREETS 

is  an  asset.     It  is  an  investment  not  a  speculation. 

Investigate  Bitulithic  before  determining  to  use  inferior  street  paving.  It  is  cheaper 
to  have  good  pavement  in  the  beginning  than  to  contract  for  cheap  constructions  and  be 
sorry  in  two  or  three  years. 

There  is  no  guess  work  in  the  construction  of  Bitulithic  pavement.  It  is  made  of 
varying  sizes  of  the  best  stone  obtainable,  combined  with  bituminous  cement  and  laid 
under  close  laboratory  supervision.  You  must  realize  that  quality  is  remembered  long 
after  the  price  is  forgotten.  The  character  of  a  city  is  indicated  by  the  condition  of  its 
streets. 

See  illustration  opposite  page  176  of  text. 

Bitulithic  is— Unequalled  in  reputation.        Bitulithic  is— Unquestioned  in  quality 

Bitulithic  is— Unrivalled  in  popularity 

Stationary  Plants  Railroad  Plants 

Semi-Portable  Plants  Portable  Plants 

We  manufacture  all  styles  of  all  capacities. 

We  can  give  you  just  what  you  want  when  you  want  it  and  the  most  for  you  money. 
See  illustration  of  Semi-portable  Plant  opposite  page  48  of  text. 

WARREN   BROTHERS  COMPANY 

Executive  Offices:  59  Temple  Place,  BOSTON,  MASS. 
DISTRICT  OFFICES: 


New  York,  N.  Y. 
50  Church  St. 


Nashville,  Tenn., 
606  First  Nat'l  Bank  Bldg, 


Chicago,  111.,  Rochester.  N.  Y.,  Los  Angeles  Cal 

10  So.  LaSalle  St.  303  Main  St  ,  West  926  Calif.  Bldg. 

Portland.  Oregon,  Phoenix,  Arizona, 

Journal  Bldg.  204  Noll  Bldg. 

Richmond,  Va.,  St.  Louis,  Mo. 

Virginia  Railway  &  Power  Bldg.        Railway  Exchange  Bldg. 


ADVERTISEMENTS. 


It  is  pre-eminently  a  high-grade  asphalt  ^ 

|     by  every  essential  test.  j. 

™  Laid  extensively  in  the  leading  cities  and  5 

on  many  state  and  county  highways. 


|  Aztec  Liquid  Asphalt  | 

For  Preserving  Roads 


I 

MM  \ 


Combines    the  features  of  a  dust   layer  5 

ft*  -// 1  i 

i     and  road  preservative  in  one.     Equally  sue-  5^ 
m     cessful  on  macadam,  dirt,  sand  or  gravel. 


The  Interocean  Oil  Co.  I 

§    The  United  States  Asphalt  Refining  Co.    I 


90  West  Street,  New  York 

Chicago  Philadelphia  Baltimore  Norfolk        1MQ 

on  II  liv^-g  i1.^1!^1!  l«^"l  il^il  li^ii  Ii^ii  I^B 


ADVER  TI  SEMEN  TS. 


Refined 
Mexican  Asphalt 

Prepared  in  various  grades  for 

Sheet  Asphalt 
Pavements 

and 

Bituminous    Macadam 
Road  Construction 

by    either    the    penetration    or 
mixing  method. 

Standard 
Asphalt  Road  Oils 

Containing  from  40%  to  60% 
asphaltum. 

Specifications  and  other   parti- 
culars on  application. 

STANDARD  OIL  COMPANY  OF  NEW  YORK 

Road  Oil  Department      26  Broadway,  New  York 


AD  VER  TISEMENTS. 


THE  HASTINGS  PAVEMENT  COMPANY 

EXECUTIVE    OFFICES 

25  BROAD  STREET  NEW  YORK  CITY 

Works  :   Hastings-on-Hudson,  New  York 

Asphalt   Block   Pavements 

See  pages  187-189  and  illustrations  opposite  page  188 

Societa     Sicula     per    1'esplotazione    dell'    Asfalto    naturale     Siciliano 

(Own  Mines  and  Works  at  Ragusa,  Sicily) 
Head  Office  at  Palermo,  Via  Girgenti    3 

Sicily  Natural  Rock  Asphalt,  Powder,  Mastic  and  Slabs 

Many  millions  of  square  metres  in  Berlin,  Paris.  Vienna,  Bucarest,  Glasgow, 

Cairo  (Egypt)  and  Athens,  also  in  Montreal  (Canada)  and  U.S.,  have  been 

laid  with  success  since  1888. 

American  Consulting  Engineer 
T.  HUGH  BOORMAN         520  E.  20th  Street,  New  York 

J.  W.  HOWARD,  C.E..E.M. 

27  Years  Experience 

Paving  Expert  Engineer 

and  Pavement  Testing  Laboratory 

EXPERT  ON  ASPHALTS  AND  THEIR  USES 

1  BROADWAY  NEW  YORK 


rr'fBJr^- 

lf%?    See 


THE  STANDARD  PAINT  CO.,      N.W  Y.A,  Bo...n,  chic.g. 


ADVER  TI  SEMEN  TS. 


INSULATINE  COMPANY,  INC. 

JOHN  A.  YATES,  C.E.,  President 
Manufacturers  of 

Waterproof  Sealing  Cements, 
Paints  and  Compounds 

No.  1  BROADWAY  NEW  YORK 

Lewis  M.  Sheridan  Benjamin  F.  Redner 

CENTRAL  CITY  ROOFING  CO. 

Original   Agents   for    Seyssel    Rock 
Asphalt  Mastic  in  Central  New  York 

See  illustration  opposite  page  76 
OFFICE  AND  YARD 

COR.  CANAL  AND  CATHERINE  STS.,    SYRACUSE,  N.  Y. 

SAN  ANTONIO  BEAUMONT  HOUSTON 

J.  B.  SMYTH,  President  CHAS.  E.  WALDEN,  Secretary 

FRANK  AI/VEY,  Treasurer 

Uvalde  Rock  Asphalt  Company 

Producers  of  the  Perfect  Natural  and  Economical  Road  and  Street 

Paving  Material 

CONTROLS  UVALDE  ROCK  ASPHALT  MINES 
1506  Dallas  Avenue  HOUSTON,  TEXAS 

See  pages  44  and  191  and  illustration  opposite  page  56 
ESTABLISHED    1860 

ESTATE   OF   J.   G.   HETZEL 

J.  G.  Hetzel's  Improved  Asphalt  Slag  Roofing 

Hetzel's  Elastic  Roof  Cement  and  Paints 

Used  throughout  U.  S.,   and  extensively  in  Europe 

See  illustration  opposite  page  160 
OFFICE  AND  WORKS 

No.  67  MAINE  STREET  NEWARK,  N.  J. 


ADVERTISEMENTS. 


QUARTERLY     PROCEEDINGS    OF 

The  American  Society  of 
Engineers,  Architects  and  Constructors 

is  one  of  the  best  mediums  for  advertising  machinery  and  materials  used 
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